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Inter-asterisk exchange (IAX) deployment scenarios in SIP-enabled networks / / Mohamed Boucadair
Inter-asterisk exchange (IAX) deployment scenarios in SIP-enabled networks / / Mohamed Boucadair
Autore Boucadair Mohamed
Pubbl/distr/stampa Chichester, U.K. : , : Wiley, , 2009
Descrizione fisica 1 online resource (275 p.)
Disciplina 004.69/5
004.695
Collana Wiley series on communications networking & distributed systems
Soggetto topico Internet telephony
Computer network protocols
ISBN 1-282-01079-4
9786612010798
0-470-74218-6
0-470-74219-4
Formato Materiale a stampa
Livello bibliografico Monografia
Lingua di pubblicazione eng
Nota di contenuto Foreword -- Terminology and Definitions -- Acronyms and Abbreviations -- Acknowledgement -- 1 Introduction -- 1.1 General Introduction -- 1.2 On Voice over IP and Telephony over IP -- 1.3 Context -- 1.4 Enhancement Strategies to Solve SIP Issues -- 1.5 IAX: Towards Lightweight Telephony Architectures -- 1.6 IAX and Standardisation -- 1.7 Rationale -- 1.8 What This Book is Not -- 1.9 Structure of the Book -- 2 The IAX Protocol at a Glance -- 2.1 What Does IAX Stand For? -- 2.2 Is IAX Specific to the Asterisk Platform? -- 2.3 What is the Difference between IAX2 and IAX? -- 2.4 Why another New VoIP Protocol? -- 2.5 How Does IAX Solve VoIP Pains? -- 2.6 How is Calls Multiplexing Achieved? -- 2.7 And What About Demultiplexing? -- 2.8 What Port Number Does IAX Use? -- 2.9 What Transport Protocol Does IAX Use? -- 2.10 Is IAX a Reliable Protocol? -- 2.11 How Does IAX Ensure Reliability? -- 2.12 Is there an IAX Registration Procedure? -- 2.13 Does IAX Registration Differ from SIP Registration? -- 2.14 How Are Media Streams Transported in IAX? -- 2.15 Is CODEC Negotiation Supported by IAX? -- 2.16 Is On-Fly CODEC Change Possible During a Call? -- 2.17 IAX: a Path-Coupled or Decoupled Protocol? -- 2.18 Can IAX be Aware of the Status of the Network Load? -- 2.19 What About Security? -- 2.20 Could IAX Devices Be Managed? -- 2.21 Is Firmware Version Updating Supported by IAX? -- 2.22 Can IAX Be Extended to Offer New Features? -- 2.23 How is an IAX Resource Identified? -- 2.24 What Does an IAX URI Look Like? -- 2.25 Is it Possible to Set a Call Involving Several IAX Servers? -- 2.26 Is it Possible to Discover the Location of an IAX Resource? -- 2.27 What Is DUNDi? -- 2.28 What Is TRIP? -- 2.29 What Is ENUM? -- References -- Further Reading -- Part One: IAX Protocol Specifications -- 3 IAX Uniform Resource Identifier -- 3.1 Introduction -- 3.2 Format of IAX Uniform Resource Identifiers -- 3.3 Examples of IAX Uniform Resource Identifiers -- 3.4 Comparing IAX Uniform Resource Identifiers.
3.5 IAX Uniform Resource Identifiers and ENUM -- References -- Further Reading -- 4 IAX Frames -- 4.1 Introduction -- 4.2 Full Frames -- 4.3 Mini Frames -- 4.4 Meta Frames -- 4.5 Encrypted Frames -- 4.6 Conclusion -- References -- Further Reading -- 5 IAX Information Elements -- 5.1 Introduction -- 5.2 List of IAX Information Elements -- 5.3 Example of IAX Information Element Traces -- References -- Further Reading -- 6 IAX Messages -- 6.1 Introduction -- 6.2 Taxonomy of IAX Messages -- 6.3 IAX Requests/Responses -- 6.4 IAX Functional Categories -- 6.5 IAX Media Frames -- 6.6 IAX Reliable/Unreliable Messages -- References -- Further Reading -- 7 IAX Connectivity Considerations -- 7.1 Introduction -- 7.2 IAX Transport Protocol -- 7.3 IAX Port Number -- 7.4 IAX Call Multiplexing and Demultiplexing -- 7.5 IAX Reliability Mechanism -- 7.6 Authentication and Encryption -- 7.7 Conclusion -- References -- Further Reading -- 8 IAX Operations -- 8.1 Introduction -- 8.2 Provisioning and Firmware Download -- 8.3 Registration -- 8.4 Call Setup -- 8.5 Call Tear-Down -- 8.6 Call Monitoring -- 8.7 Call Optimisation -- 8.8 Conclusion -- References -- Further Reading -- Part Two: Discussion and Analysis -- 9 IAX and Advanced Services -- 9.1 Introduction -- 9.2 CODEC Negotiation -- 9.3 Video Sessions -- 9.4 Negotiation of Several Media Types in the Same IAX Session -- 9.5 Presence Services -- 9.6 Instant Messaging -- 9.7 Topology Hiding -- 9.8 Mobility -- 9.9 Miscellaneous -- 9.10 Conclusion -- References -- Further Reading -- 10 Multi-IAX Servers Environment -- 10.1 Introduction -- 10.2 Focus -- 10.3 Discovery of IAX Resources -- 10.4 Setting End-to-End Calls -- 10.5 Load Balancing -- 10.6 Path-Coupled and Path-Decoupled Discussion -- 10.7 Forking -- 10.8 Route Symmetry -- 10.9 Conclusion -- References -- 11 IAX and NAT Traversal -- 11.1 Introduction -- 11.2 Structure -- 11.3 NAT Types -- 11.4 IAX and NAT Traversal Discussion -- 11.5 Operational Considerations -- 11.6 Conclusion -- References.
Further Reading -- 12 IAX and Peer-to-Peer Deployment Scenarios -- 12.1 Introduction -- 12.2 Scope -- 12.3 A P2P Solution for Corporate Customers -- 12.4 Conclusion -- References -- Further Reading -- 13 IAX and IPv6 -- 13.1 Introduction -- 13.2 Context and Assumptions -- 13.3 Service Migration to IPv6 -- 13.4 Structure -- 13.5 The IP Address Exhaustion Problem -- 13.6 IPv6: a Long-Term Solution -- 13.7 Why IPv6 May Be Problematic for Telephony Signalling Protocols: the SIP Example -- 13.8 IAX: an IP Version-Agnostic Protocol? -- 13.9 Deployment of IAX Services in a 'Pure' IPv6 Environment -- 13.10 Heterogeneous Environment -- 13.11 Conclusion -- References -- Further Reading -- 14 IAX: Towards a Lightweight SBC? -- 14.1 Introduction -- 14.2 IP Telephony Administrative Domain -- 14.3 Deployment Scenarios -- 14.4 Deployment Contexts -- 14.5 Service Limitations Caused by SBCs -- 14.6 Functional Decomposition -- 14.7 Taxonomy of SBC Functions in an SIP Environment -- 14.8 Validity of these Functions in an IAX Architecture -- 14.9 Conclusion -- References -- Further Reading -- Part Three: Deployment Scenarios in SIP-Based Environments -- 15 Scenarios for the Deployment of IAX-Based Conversational Services -- 15.1 SIP Complications -- 15.2 Structure -- 15.3 Beyond the 'SIP-Centric' Era -- 15.4 Methodology -- 15.5 Overall Context -- 15.6 Architectural Requirements -- 15.7 Brief Comparison -- 15.8 Taxonomy -- 15.9 Introducing IAX into Operational Networks -- 15.10 Conclusion. / -- References -- 16 IAX in the Access Segment of SIP-Based Service Architectures -- 16.1 Introduction -- 16.2 A 'High-Level' Description of the Interworking Function -- 16.3 Examples of Call Flows -- 16.4 Bandwidth Optimisation: An Extension to SIP -- 16.5 Conclusion -- References -- 17 Validation Scenario -- 17.1 Overview -- 17.2 Configuring Asterisk Servers -- 17.3 Configuring the SIP Express Router (SER) -- 17.4 User Agent Configuration -- 17.5 Conclusion -- Further Reading -- Index.
Record Nr. UNINA-9910830232403321
Boucadair Mohamed  
Chichester, U.K. : , : Wiley, , 2009
Materiale a stampa
Lo trovi qui: Univ. Federico II
Opac: Controlla la disponibilità qui
Inter-asterisk exchange (IAX) deployment scenarios in SIP-enabled networks / / Mohamed Boucadair
Inter-asterisk exchange (IAX) deployment scenarios in SIP-enabled networks / / Mohamed Boucadair
Autore Boucadair Mohamed
Pubbl/distr/stampa Chichester, U.K., : Wiley, 2009
Descrizione fisica 1 online resource (275 p.)
Disciplina 004.69/5
004.695
Collana Wiley series in communications networking & distributed systems
Soggetto topico Internet telephony
Computer network protocols
ISBN 1-282-01079-4
9786612010798
0-470-74218-6
0-470-74219-4
Formato Materiale a stampa
Livello bibliografico Monografia
Lingua di pubblicazione eng
Nota di contenuto Foreword -- Terminology and Definitions -- Acronyms and Abbreviations -- Acknowledgement -- 1 Introduction -- 1.1 General Introduction -- 1.2 On Voice over IP and Telephony over IP -- 1.3 Context -- 1.4 Enhancement Strategies to Solve SIP Issues -- 1.5 IAX: Towards Lightweight Telephony Architectures -- 1.6 IAX and Standardisation -- 1.7 Rationale -- 1.8 What This Book is Not -- 1.9 Structure of the Book -- 2 The IAX Protocol at a Glance -- 2.1 What Does IAX Stand For? -- 2.2 Is IAX Specific to the Asterisk Platform? -- 2.3 What is the Difference between IAX2 and IAX? -- 2.4 Why another New VoIP Protocol? -- 2.5 How Does IAX Solve VoIP Pains? -- 2.6 How is Calls Multiplexing Achieved? -- 2.7 And What About Demultiplexing? -- 2.8 What Port Number Does IAX Use? -- 2.9 What Transport Protocol Does IAX Use? -- 2.10 Is IAX a Reliable Protocol? -- 2.11 How Does IAX Ensure Reliability? -- 2.12 Is there an IAX Registration Procedure? -- 2.13 Does IAX Registration Differ from SIP Registration? -- 2.14 How Are Media Streams Transported in IAX? -- 2.15 Is CODEC Negotiation Supported by IAX? -- 2.16 Is On-Fly CODEC Change Possible During a Call? -- 2.17 IAX: a Path-Coupled or Decoupled Protocol? -- 2.18 Can IAX be Aware of the Status of the Network Load? -- 2.19 What About Security? -- 2.20 Could IAX Devices Be Managed? -- 2.21 Is Firmware Version Updating Supported by IAX? -- 2.22 Can IAX Be Extended to Offer New Features? -- 2.23 How is an IAX Resource Identified? -- 2.24 What Does an IAX URI Look Like? -- 2.25 Is it Possible to Set a Call Involving Several IAX Servers? -- 2.26 Is it Possible to Discover the Location of an IAX Resource? -- 2.27 What Is DUNDi? -- 2.28 What Is TRIP? -- 2.29 What Is ENUM? -- References -- Further Reading -- Part One: IAX Protocol Specifications -- 3 IAX Uniform Resource Identifier -- 3.1 Introduction -- 3.2 Format of IAX Uniform Resource Identifiers -- 3.3 Examples of IAX Uniform Resource Identifiers -- 3.4 Comparing IAX Uniform Resource Identifiers.
3.5 IAX Uniform Resource Identifiers and ENUM -- References -- Further Reading -- 4 IAX Frames -- 4.1 Introduction -- 4.2 Full Frames -- 4.3 Mini Frames -- 4.4 Meta Frames -- 4.5 Encrypted Frames -- 4.6 Conclusion -- References -- Further Reading -- 5 IAX Information Elements -- 5.1 Introduction -- 5.2 List of IAX Information Elements -- 5.3 Example of IAX Information Element Traces -- References -- Further Reading -- 6 IAX Messages -- 6.1 Introduction -- 6.2 Taxonomy of IAX Messages -- 6.3 IAX Requests/Responses -- 6.4 IAX Functional Categories -- 6.5 IAX Media Frames -- 6.6 IAX Reliable/Unreliable Messages -- References -- Further Reading -- 7 IAX Connectivity Considerations -- 7.1 Introduction -- 7.2 IAX Transport Protocol -- 7.3 IAX Port Number -- 7.4 IAX Call Multiplexing and Demultiplexing -- 7.5 IAX Reliability Mechanism -- 7.6 Authentication and Encryption -- 7.7 Conclusion -- References -- Further Reading -- 8 IAX Operations -- 8.1 Introduction -- 8.2 Provisioning and Firmware Download -- 8.3 Registration -- 8.4 Call Setup -- 8.5 Call Tear-Down -- 8.6 Call Monitoring -- 8.7 Call Optimisation -- 8.8 Conclusion -- References -- Further Reading -- Part Two: Discussion and Analysis -- 9 IAX and Advanced Services -- 9.1 Introduction -- 9.2 CODEC Negotiation -- 9.3 Video Sessions -- 9.4 Negotiation of Several Media Types in the Same IAX Session -- 9.5 Presence Services -- 9.6 Instant Messaging -- 9.7 Topology Hiding -- 9.8 Mobility -- 9.9 Miscellaneous -- 9.10 Conclusion -- References -- Further Reading -- 10 Multi-IAX Servers Environment -- 10.1 Introduction -- 10.2 Focus -- 10.3 Discovery of IAX Resources -- 10.4 Setting End-to-End Calls -- 10.5 Load Balancing -- 10.6 Path-Coupled and Path-Decoupled Discussion -- 10.7 Forking -- 10.8 Route Symmetry -- 10.9 Conclusion -- References -- 11 IAX and NAT Traversal -- 11.1 Introduction -- 11.2 Structure -- 11.3 NAT Types -- 11.4 IAX and NAT Traversal Discussion -- 11.5 Operational Considerations -- 11.6 Conclusion -- References.
Further Reading -- 12 IAX and Peer-to-Peer Deployment Scenarios -- 12.1 Introduction -- 12.2 Scope -- 12.3 A P2P Solution for Corporate Customers -- 12.4 Conclusion -- References -- Further Reading -- 13 IAX and IPv6 -- 13.1 Introduction -- 13.2 Context and Assumptions -- 13.3 Service Migration to IPv6 -- 13.4 Structure -- 13.5 The IP Address Exhaustion Problem -- 13.6 IPv6: a Long-Term Solution -- 13.7 Why IPv6 May Be Problematic for Telephony Signalling Protocols: the SIP Example -- 13.8 IAX: an IP Version-Agnostic Protocol? -- 13.9 Deployment of IAX Services in a 'Pure' IPv6 Environment -- 13.10 Heterogeneous Environment -- 13.11 Conclusion -- References -- Further Reading -- 14 IAX: Towards a Lightweight SBC? -- 14.1 Introduction -- 14.2 IP Telephony Administrative Domain -- 14.3 Deployment Scenarios -- 14.4 Deployment Contexts -- 14.5 Service Limitations Caused by SBCs -- 14.6 Functional Decomposition -- 14.7 Taxonomy of SBC Functions in an SIP Environment -- 14.8 Validity of these Functions in an IAX Architecture -- 14.9 Conclusion -- References -- Further Reading -- Part Three: Deployment Scenarios in SIP-Based Environments -- 15 Scenarios for the Deployment of IAX-Based Conversational Services -- 15.1 SIP Complications -- 15.2 Structure -- 15.3 Beyond the 'SIP-Centric' Era -- 15.4 Methodology -- 15.5 Overall Context -- 15.6 Architectural Requirements -- 15.7 Brief Comparison -- 15.8 Taxonomy -- 15.9 Introducing IAX into Operational Networks -- 15.10 Conclusion. / -- References -- 16 IAX in the Access Segment of SIP-Based Service Architectures -- 16.1 Introduction -- 16.2 A 'High-Level' Description of the Interworking Function -- 16.3 Examples of Call Flows -- 16.4 Bandwidth Optimisation: An Extension to SIP -- 16.5 Conclusion -- References -- 17 Validation Scenario -- 17.1 Overview -- 17.2 Configuring Asterisk Servers -- 17.3 Configuring the SIP Express Router (SER) -- 17.4 User Agent Configuration -- 17.5 Conclusion -- Further Reading -- Index.
Record Nr. UNINA-9910876816403321
Boucadair Mohamed  
Chichester, U.K., : Wiley, 2009
Materiale a stampa
Lo trovi qui: Univ. Federico II
Opac: Controlla la disponibilità qui
Securing VoIP : keeping your VoIP network safe / / Regis J. (Bud) Bates ; acquiring editor, Steve Elliot ; designer, Greg Harris
Securing VoIP : keeping your VoIP network safe / / Regis J. (Bud) Bates ; acquiring editor, Steve Elliot ; designer, Greg Harris
Autore Bates Regis J., Bud
Edizione [1st edition]
Pubbl/distr/stampa Waltham, Massachusetts : , : Syngress, , 2015
Descrizione fisica 1 online resource (222 p.)
Disciplina 004.695
Soggetto topico Internet telephony - Security measures
Soggetto genere / forma Electronic books.
ISBN 0-12-417122-2
Formato Materiale a stampa
Livello bibliografico Monografia
Lingua di pubblicazione eng
Nota di contenuto Cover; Title Page; Copyright Page; Contents; Technical editor biography; About the author; Expertise; Publications; Books; Articles; Acknowledgments; Chapter 1 - Introduction; Securing Voice over Internet Protocol (VoIP): keeping your network safe; History of telephony; History of the Internet Protocol; What goes around comes around; VoIP network and potential problems; The benefits of VoIP; Some initial thoughts on VoIP; What are the reasons for the VoIP hacking attempts; The need for VoIP security; Need for security and causes; Technology; Policy; Terms and attacks; Other vulnerabilities
What is at riskCan a call be eavesdropped?; There is no Holy Grail out there; Summary; Chapter 2 - Policies; What is the problem?; The call control channel - hijacking; Softphone issues; Denial-of-service attacks; Security concerns; Security policy needs; Vulnerability detection and auditing; Is the system vulnerable?; Chapter 3 - VoIP virtual private networks (VPNs); Virtual private networks (VPNs) and encryption; What is a VPN?; The possible VPN solutions; What a VPN can offer; What everyone expects from securing VoIP; What is the impact?; Creating the VPN; IPSec used for site-to-site VPNs
Disadvantages of IPSec VPN site-to-site tunnelsSummary; Chapter 4 - Cryptography solutions; Cryptography solutions; What is cryptography and encryption?; Early ciphers used; Digital signatures; Leads to a public key infrastructure; X.509 certificates; Digital certificate servers; Installing certificates on the devices; Summary; Chapter 5 - Authentication; Authentication defined; Details of 802.1x authentication; Use a VoIP-enabled firewall; Use 802.1X authentication for IP phones; Attacking VoIP Authentication; Encrypt the traffic; Authentication on wireless networks; Summary
Chapter 6 - Other protocolsOther protocols; Overview of Real-Time Transport Protocol and Real-Time Transport Control Protocol (RTCP); RTCP; Function of Secure RTP; Enter SRTP and SRTCP; SRTP framework; Secure RTP using ZRTP; Mikey; Modes of MIKEY; Preshared key transfer; Public key transfer; Public key with Diffie-Hellman exchange; Transport protocols; Signaling: Session Initiation Protocol; Attacks on SIP; Denial of service; BYE; Authentication; Secure SIP; Transport and network layer security; Summary; Chapter 7 - The business case for securing VoIP; Before we start
Overview of the RFC 2196Internal issues; Toll fraud - a big threat; Summary; Chapter 8 - Approaches to VoIP security; Before we start; Build it in layers; Some best practices for infrastructure security; Integrating network security; Additional thoughts and items; Registration spoofing; Summary; Chapter 9 - Final thoughts; Before we start; What we have already covered; Vendor issues; Controlling the risks; PBX best practices; Summary; Index
Record Nr. UNINA-9910463801603321
Bates Regis J., Bud  
Waltham, Massachusetts : , : Syngress, , 2015
Materiale a stampa
Lo trovi qui: Univ. Federico II
Opac: Controlla la disponibilità qui
Securing VoIP : keeping your VoIP network safe / / Regis J. (Bud) Bates ; acquiring editor, Steve Elliot ; designer, Greg Harris
Securing VoIP : keeping your VoIP network safe / / Regis J. (Bud) Bates ; acquiring editor, Steve Elliot ; designer, Greg Harris
Autore Bates Regis J., Bud
Edizione [1st edition]
Pubbl/distr/stampa Waltham, Massachusetts : , : Syngress, , 2015
Descrizione fisica 1 online resource (222 p.)
Disciplina 004.695
Soggetto topico Internet telephony - Security measures
ISBN 0-12-417122-2
Formato Materiale a stampa
Livello bibliografico Monografia
Lingua di pubblicazione eng
Nota di contenuto Cover; Title Page; Copyright Page; Contents; Technical editor biography; About the author; Expertise; Publications; Books; Articles; Acknowledgments; Chapter 1 - Introduction; Securing Voice over Internet Protocol (VoIP): keeping your network safe; History of telephony; History of the Internet Protocol; What goes around comes around; VoIP network and potential problems; The benefits of VoIP; Some initial thoughts on VoIP; What are the reasons for the VoIP hacking attempts; The need for VoIP security; Need for security and causes; Technology; Policy; Terms and attacks; Other vulnerabilities
What is at riskCan a call be eavesdropped?; There is no Holy Grail out there; Summary; Chapter 2 - Policies; What is the problem?; The call control channel - hijacking; Softphone issues; Denial-of-service attacks; Security concerns; Security policy needs; Vulnerability detection and auditing; Is the system vulnerable?; Chapter 3 - VoIP virtual private networks (VPNs); Virtual private networks (VPNs) and encryption; What is a VPN?; The possible VPN solutions; What a VPN can offer; What everyone expects from securing VoIP; What is the impact?; Creating the VPN; IPSec used for site-to-site VPNs
Disadvantages of IPSec VPN site-to-site tunnelsSummary; Chapter 4 - Cryptography solutions; Cryptography solutions; What is cryptography and encryption?; Early ciphers used; Digital signatures; Leads to a public key infrastructure; X.509 certificates; Digital certificate servers; Installing certificates on the devices; Summary; Chapter 5 - Authentication; Authentication defined; Details of 802.1x authentication; Use a VoIP-enabled firewall; Use 802.1X authentication for IP phones; Attacking VoIP Authentication; Encrypt the traffic; Authentication on wireless networks; Summary
Chapter 6 - Other protocolsOther protocols; Overview of Real-Time Transport Protocol and Real-Time Transport Control Protocol (RTCP); RTCP; Function of Secure RTP; Enter SRTP and SRTCP; SRTP framework; Secure RTP using ZRTP; Mikey; Modes of MIKEY; Preshared key transfer; Public key transfer; Public key with Diffie-Hellman exchange; Transport protocols; Signaling: Session Initiation Protocol; Attacks on SIP; Denial of service; BYE; Authentication; Secure SIP; Transport and network layer security; Summary; Chapter 7 - The business case for securing VoIP; Before we start
Overview of the RFC 2196Internal issues; Toll fraud - a big threat; Summary; Chapter 8 - Approaches to VoIP security; Before we start; Build it in layers; Some best practices for infrastructure security; Integrating network security; Additional thoughts and items; Registration spoofing; Summary; Chapter 9 - Final thoughts; Before we start; What we have already covered; Vendor issues; Controlling the risks; PBX best practices; Summary; Index
Record Nr. UNINA-9910787921403321
Bates Regis J., Bud  
Waltham, Massachusetts : , : Syngress, , 2015
Materiale a stampa
Lo trovi qui: Univ. Federico II
Opac: Controlla la disponibilità qui
Securing VoIP : keeping your VoIP network safe / / Regis J. (Bud) Bates ; acquiring editor, Steve Elliot ; designer, Greg Harris
Securing VoIP : keeping your VoIP network safe / / Regis J. (Bud) Bates ; acquiring editor, Steve Elliot ; designer, Greg Harris
Autore Bates Regis J., Bud
Edizione [1st edition]
Pubbl/distr/stampa Waltham, Massachusetts : , : Syngress, , 2015
Descrizione fisica 1 online resource (222 p.)
Disciplina 004.695
Soggetto topico Internet telephony - Security measures
ISBN 0-12-417122-2
Formato Materiale a stampa
Livello bibliografico Monografia
Lingua di pubblicazione eng
Nota di contenuto Cover; Title Page; Copyright Page; Contents; Technical editor biography; About the author; Expertise; Publications; Books; Articles; Acknowledgments; Chapter 1 - Introduction; Securing Voice over Internet Protocol (VoIP): keeping your network safe; History of telephony; History of the Internet Protocol; What goes around comes around; VoIP network and potential problems; The benefits of VoIP; Some initial thoughts on VoIP; What are the reasons for the VoIP hacking attempts; The need for VoIP security; Need for security and causes; Technology; Policy; Terms and attacks; Other vulnerabilities
What is at riskCan a call be eavesdropped?; There is no Holy Grail out there; Summary; Chapter 2 - Policies; What is the problem?; The call control channel - hijacking; Softphone issues; Denial-of-service attacks; Security concerns; Security policy needs; Vulnerability detection and auditing; Is the system vulnerable?; Chapter 3 - VoIP virtual private networks (VPNs); Virtual private networks (VPNs) and encryption; What is a VPN?; The possible VPN solutions; What a VPN can offer; What everyone expects from securing VoIP; What is the impact?; Creating the VPN; IPSec used for site-to-site VPNs
Disadvantages of IPSec VPN site-to-site tunnelsSummary; Chapter 4 - Cryptography solutions; Cryptography solutions; What is cryptography and encryption?; Early ciphers used; Digital signatures; Leads to a public key infrastructure; X.509 certificates; Digital certificate servers; Installing certificates on the devices; Summary; Chapter 5 - Authentication; Authentication defined; Details of 802.1x authentication; Use a VoIP-enabled firewall; Use 802.1X authentication for IP phones; Attacking VoIP Authentication; Encrypt the traffic; Authentication on wireless networks; Summary
Chapter 6 - Other protocolsOther protocols; Overview of Real-Time Transport Protocol and Real-Time Transport Control Protocol (RTCP); RTCP; Function of Secure RTP; Enter SRTP and SRTCP; SRTP framework; Secure RTP using ZRTP; Mikey; Modes of MIKEY; Preshared key transfer; Public key transfer; Public key with Diffie-Hellman exchange; Transport protocols; Signaling: Session Initiation Protocol; Attacks on SIP; Denial of service; BYE; Authentication; Secure SIP; Transport and network layer security; Summary; Chapter 7 - The business case for securing VoIP; Before we start
Overview of the RFC 2196Internal issues; Toll fraud - a big threat; Summary; Chapter 8 - Approaches to VoIP security; Before we start; Build it in layers; Some best practices for infrastructure security; Integrating network security; Additional thoughts and items; Registration spoofing; Summary; Chapter 9 - Final thoughts; Before we start; What we have already covered; Vendor issues; Controlling the risks; PBX best practices; Summary; Index
Record Nr. UNINA-9910807049603321
Bates Regis J., Bud  
Waltham, Massachusetts : , : Syngress, , 2015
Materiale a stampa
Lo trovi qui: Univ. Federico II
Opac: Controlla la disponibilità qui
VoIP and PBX Security and Forensics : A Practical Approach / / by Iosif I. Androulidakis
VoIP and PBX Security and Forensics : A Practical Approach / / by Iosif I. Androulidakis
Autore Androulidakis Iosif I
Edizione [2nd ed. 2016.]
Pubbl/distr/stampa Cham : , : Springer International Publishing : , : Imprint : Springer, , 2016
Descrizione fisica 1 online resource (112 p.)
Disciplina 004.695
Collana SpringerBriefs in Electrical and Computer Engineering
Soggetto topico Electrical engineering
Computer security
System safety
Forensic science
Communications Engineering, Networks
Systems and Data Security
Security Science and Technology
Forensic Science
ISBN 3-319-29721-X
Formato Materiale a stampa
Livello bibliografico Monografia
Lingua di pubblicazione eng
Nota di contenuto Introduction -- Confidentiality, Integrity, and Availability Threats in PBXs -- PBX Technical Details -- PBX Security -- PBX Forensics -- Conclusion.
Record Nr. UNINA-9910254251003321
Androulidakis Iosif I  
Cham : , : Springer International Publishing : , : Imprint : Springer, , 2016
Materiale a stampa
Lo trovi qui: Univ. Federico II
Opac: Controlla la disponibilità qui
VoIP and unified communications : internet telephony and the future voice network / / William A. Flanagan
VoIP and unified communications : internet telephony and the future voice network / / William A. Flanagan
Autore Flanagan William A.
Edizione [1st edition]
Pubbl/distr/stampa Hoboken, New Jersey : , : Wiley, , c2012
Descrizione fisica 1 online resource (316 p.)
Disciplina 004.695
621.385
Soggetto topico Internet telephony
Multimedia communications
ISBN 1-280-59175-7
9786613621580
1-118-16603-5
1-118-16604-3
1-118-16601-9
Classificazione TEC041000
Formato Materiale a stampa
Livello bibliografico Monografia
Lingua di pubblicazione eng
Nota di contenuto -- Preface xiii -- Acknowledgments xv -- 1 IP Technology Disrupts Voice Telephony 1 -- 1.1 Introduction to the Public Switched Telephone Network 1 -- 1.2 The Digital PSTN 2 -- 1.3 The Packet Revolution in Telephony 8 -- 1.3.1 Summary of Packet Switching 9 -- 1.3.2 Link Capacity: TDM versus Packets 11 -- 1.3.3 VoIP and “The Cloud” 13 -- IN SHORT: Reading Network Drawings 14 -- 2 Traditional Telephones Still Set Expectations 17 -- 2.1 Availability: How the Bell System Ensured Service 18 -- 2.2 Call Completion 19 -- 2.3 Sound Quality: Encoding for Recognizable Voices 20 -- 2.4 Low Latency 23 -- 2.5 Call Setup Delays 24 -- 2.6 Impairments Controlled: Echo, Singing, Distortion, Noise 25 -- 3 From Circuits to Packets 27 -- 3.1 Data and Signaling Preceded Voice 27 -- 3.1.1 X.25 Packet Data Service 27 -- 3.1.2 SS7: PSTN Signaling on Packets 28 -- 3.1.3 ISDN 29 -- 3.2 Putting Voice into Packets 30 -- 3.2.1 Voice Encoding 31 -- 3.2.2 Dicing and Splicing Voice Streams 32 -- 3.2.3 The Latency Budget 33 -- 4 Packet Transmission and Switching 37 -- 4.1 The Physical Layer: Transmission 39 -- IN SHORT: The Endian Wars 40 -- 4.2 Data Link Protocols 41 -- 4.3 IP, the Network Protocol 43 -- 4.4 Layer 4 Transport Protocols 47 -- 4.4.1 Transmission Control Protocol 47 -- 4.4.2 User Datagram Protocol 50 -- 4.4.3 Stream Control Transmission Protocol 51 -- 4.5 Higher Layer Processes 54 -- 4.5.1 RTP 54 -- 4.5.2 RTCP 57 -- 4.5.3 Multiplexing RTP and RTCP on One UDP Port 58 -- 4.5.4 RTP Mixers and Translators 59 -- 4.5.5 Layered Encoding 60 -- 4.5.6 Profiles for Audio and Video Conferences 60 -- 4.5.7 Security via Encryption 61 -- IN SHORT: Public Key Infrastructure (PKI) 62 -- 4.6 Saving Bandwidth 64 -- 4.6.1 Voice Compression 64 -- 4.6.2 Header Compression 66 -- 4.6.3 Silence Suppression, VAD 67 -- 4.6.4 Sub-Packet Multiplexing 69 -- 4.6.5 Protocol and Codec Selection 70 -- 4.7 Differences: Circuit versus Packet Switched 71 -- 4.7.1 Power to the Desktop Phone 71 -- 4.7.2 Phone as Computer and Computer as Phone 72.
4.7.3 Length of a Phone Line 72 -- 4.7.4 Scaling to Large Size 75 -- 4.7.5 Software Ownership and Licenses 75 -- 5 VoIP Signaling and Call Processing 77 -- 5.1 What Packet Voice and UC Systems Share 78 -- 5.2 Session Initiation Protocol (SIP) 80 -- 5.2.1 SIP Architecture 81 -- 5.2.2 SIP Messages 88 -- 5.2.3 SIP Header Fields and Behaviors 94 -- 5.3 Session Description Protocol 101 -- IN SHORT: ABNF 104 -- 5.4 Media Gateway Control Protocol 107 -- 5.4.1 MGW Functions 107 -- 5.4.2 MGW Connection Model 110 -- 5.4.3 Megaco Procedures 112 -- 5.4.4 Megaco Details 115 -- 5.4.5 Signaling Conversion 119 -- 5.4.6 Voice Transcoding 119 -- 5.5 H.323 120 -- 5.5.1 H.323 Architecture 121 -- 5.5.2 Gatekeeper 123 -- 5.5.3 Gateway 126 -- 5.5.4 Terminal 126 -- 5.5.5 Multipoint Control Unit 127 -- 5.5.6 Call Procedures 128 -- 5.6 Directory Services 134 -- 5.6.1 Domain Name Service (DNS) 134 -- 5.6.2 ENUM 135 -- 6 VoIP and Unified Communications Define the Future 139 -- 6.1 Voice as Before, with Additions 139 -- 6.2 Legacy Services to Keep and Improve with VoIP 140 -- 6.2.1 Flexible Call Routing and 800 Numbers 141 -- 6.2.2 Call on Hold 141 -- 6.2.3 Call Transfer 142 -- 6.2.4 Call Forwarding 142 -- 6.2.5 Audio Conferencing 142 -- 6.2.6 Video Conferencing 143 -- 6.2.7 Local Number Portability 144 -- 6.2.8 Direct Inward Dialing, Dialed Number Indication 144 -- 6.2.9 CallMessage Waiting 145 -- 6.2.10 Call Recording 146 -- 6.2.11 Emergency Calling (E911) 146 -- 6.2.12 Tracking IP Phone Locations for E911 150 -- 6.3 Facsimile Transmission 153 -- 6.3.1 Facsimile on the PSTN 153 -- 6.3.2 Real-Time Fax over IP: Fax Relay or T.38 155 -- 6.3.3 Store-and-Forward Fax Handling 160 -- 6.3.4 IP Faxing over the PSTN 161 -- 6.4 Phone Features Added with VoIPUC 162 -- 6.4.1 Presence 163 -- 6.4.2 Forking 163 -- 6.4.3 Voicemail1/4eMail 163 -- 6.4.4 SMS Integration 164 -- 6.4.5 Instant Messaging 165 -- 6.4.6 Webinar Broadcasts 168 -- 6.4.7 Telepresence 168 -- 6.4.8 More UC Features to Consider 168 -- 7 How VoIP and UC Impact the Network 171.
7.1 Space, Power, and Cooling 171 -- 7.2 Priority for Voice, Video, Fax Packets 172 -- 7.3 Packets per Second 174 -- 7.4 Bandwidth 174 -- 7.5 Security Issues 175 -- 7.5.1 Eavesdropping and vLAN Hopping 176 -- 7.5.2 Access Controls for Users and Connections 176 -- 7.5.3 Modems 177 -- 7.5.4 DNS Cache Poisoning 177 -- IN SHORT: Earliest Instance of DNS Cache Poisoning 179 -- 7.5.5 Toll Fraud 179 -- 7.5.6 Pay-per-Call Scams 179 -- 7.5.7 Vishing 180 -- 7.5.8 SIP ScanningSPIT 180 -- 7.5.9 Opening the Firewall to Incoming Voice 181 -- 7.6 First Migration Steps While Keeping Legacy Equipment 181 -- 7.6.1 Circuit-Switched PBX 182 -- 7.6.2 Digital Phones 182 -- 7.6.3 Analog Phones and FX Service 183 -- 7.6.4 Facsimile Machines 184 -- 7.6.5 Modems 185 -- 8 Interconnections to Global Services 187 -- 8.1 Media Gateways 188 -- 8.2 SIP Trunking 192 -- 8.3 Operating VoIP Across Network Address Translation 196 -- 8.3.1 Failures of SIP, SDP (Signaling) 199 -- 8.3.2 Failures of RTP (Media) 199 -- 8.3.3 Solutions 200 -- 8.3.4 STUN: Session Traversal Utilities for NAT 201 -- 8.3.5 TURN: Traversal Using Relays around NAT 204 -- 8.3.6 ICE: Interactive Connectivity Establishment 206 -- 8.4 Session Border Controller 207 -- 8.4.1 Enterprise SBC 209 -- 8.4.2 Carrier SBC 210 -- 8.5 Supporting Multiple-Carrier Connections 212 -- 8.6 Mobility and Wireless Access 213 -- 8.6.1 VoIP on Wireless LANsWi-Fi 213 -- 8.6.2 Integration of Wi-Fi and Cellular Services 214 -- 8.6.3 Packet Voice on Mobile Broadband: WiMAX, LTE 214 -- 8.6.4 Radio over VoIP 215 -- IN SHORT: E&M Voice Signaling 216 -- 9 Network Management for VoIP and UC 217 -- 9.1 Starting Right 218 -- 9.1.1 Acceptance Testing 219 -- 9.1.2 Configuration Management and Governance 220 -- 9.1.3 Privilege Setting 220 -- 9.2 Continuous Monitoring and Management 221 -- 9.2.1 NMS Software 222 -- 9.2.2 Simple Network Management Protocol 223 -- 9.2.3 Web Interface 224 -- 9.2.4 Server Logging 224 -- 9.2.5 Software Maintenance 225 -- 9.2.6 Quality of ServiceExperience Monitoring 225.
9.2.7 Validate Adjustments and Optimization 226 -- 9.3 Troubleshooting and Repair 226 -- 9.3.1 Methods 226 -- 9.3.2 Software Tools 228 -- 9.3.3 Test Instruments 229 -- 10 Cost Analysis and Payback Calculation 231 -- 11 Examples of Hardware and Software 237 -- 11.1 IP Phones 237 -- 11.2 Gateways 240 -- 11.3 Session Border Controllers 242 -- 11.4 Call-Switching Servers 244 -- 11.4.1 IP PBX 246 -- 11.4.2 Conference BridgesControllers 248 -- 11.4.3 Call Recorder 250 -- 11.5 Hosted VoIPUC Service 251 -- 11.6 Management SystemsWorkstations 252 -- 12 Appendixes 253 -- 12.1 Acronyms and Definitions 253 -- 12.2 Reference Documents 268 -- 12.2.1 RFCs 268 -- 12.2.2 ITU Recommendations 272 -- 12.2.3 Other Sources 272 -- 12.3 Message and Error Codes 274 -- Index 277.
Record Nr. UNINA-9910141343203321
Flanagan William A.  
Hoboken, New Jersey : , : Wiley, , c2012
Materiale a stampa
Lo trovi qui: Univ. Federico II
Opac: Controlla la disponibilità qui
VoIP and unified communications : internet telephony and the future voice network / / William A. Flanagan
VoIP and unified communications : internet telephony and the future voice network / / William A. Flanagan
Autore Flanagan William A
Edizione [1st edition]
Pubbl/distr/stampa Hoboken, N.J., : Wiley, c2012
Descrizione fisica 1 online resource (316 p.)
Disciplina 004.695
621.385
Soggetto topico Internet telephony
Multimedia communications
ISBN 1-280-59175-7
9786613621580
1-118-16603-5
1-118-16604-3
1-118-16601-9
Classificazione TEC041000
Formato Materiale a stampa
Livello bibliografico Monografia
Lingua di pubblicazione eng
Nota di contenuto -- Preface xiii -- Acknowledgments xv -- 1 IP Technology Disrupts Voice Telephony 1 -- 1.1 Introduction to the Public Switched Telephone Network 1 -- 1.2 The Digital PSTN 2 -- 1.3 The Packet Revolution in Telephony 8 -- 1.3.1 Summary of Packet Switching 9 -- 1.3.2 Link Capacity: TDM versus Packets 11 -- 1.3.3 VoIP and “The Cloud” 13 -- IN SHORT: Reading Network Drawings 14 -- 2 Traditional Telephones Still Set Expectations 17 -- 2.1 Availability: How the Bell System Ensured Service 18 -- 2.2 Call Completion 19 -- 2.3 Sound Quality: Encoding for Recognizable Voices 20 -- 2.4 Low Latency 23 -- 2.5 Call Setup Delays 24 -- 2.6 Impairments Controlled: Echo, Singing, Distortion, Noise 25 -- 3 From Circuits to Packets 27 -- 3.1 Data and Signaling Preceded Voice 27 -- 3.1.1 X.25 Packet Data Service 27 -- 3.1.2 SS7: PSTN Signaling on Packets 28 -- 3.1.3 ISDN 29 -- 3.2 Putting Voice into Packets 30 -- 3.2.1 Voice Encoding 31 -- 3.2.2 Dicing and Splicing Voice Streams 32 -- 3.2.3 The Latency Budget 33 -- 4 Packet Transmission and Switching 37 -- 4.1 The Physical Layer: Transmission 39 -- IN SHORT: The Endian Wars 40 -- 4.2 Data Link Protocols 41 -- 4.3 IP, the Network Protocol 43 -- 4.4 Layer 4 Transport Protocols 47 -- 4.4.1 Transmission Control Protocol 47 -- 4.4.2 User Datagram Protocol 50 -- 4.4.3 Stream Control Transmission Protocol 51 -- 4.5 Higher Layer Processes 54 -- 4.5.1 RTP 54 -- 4.5.2 RTCP 57 -- 4.5.3 Multiplexing RTP and RTCP on One UDP Port 58 -- 4.5.4 RTP Mixers and Translators 59 -- 4.5.5 Layered Encoding 60 -- 4.5.6 Profiles for Audio and Video Conferences 60 -- 4.5.7 Security via Encryption 61 -- IN SHORT: Public Key Infrastructure (PKI) 62 -- 4.6 Saving Bandwidth 64 -- 4.6.1 Voice Compression 64 -- 4.6.2 Header Compression 66 -- 4.6.3 Silence Suppression, VAD 67 -- 4.6.4 Sub-Packet Multiplexing 69 -- 4.6.5 Protocol and Codec Selection 70 -- 4.7 Differences: Circuit versus Packet Switched 71 -- 4.7.1 Power to the Desktop Phone 71 -- 4.7.2 Phone as Computer and Computer as Phone 72.
4.7.3 Length of a Phone Line 72 -- 4.7.4 Scaling to Large Size 75 -- 4.7.5 Software Ownership and Licenses 75 -- 5 VoIP Signaling and Call Processing 77 -- 5.1 What Packet Voice and UC Systems Share 78 -- 5.2 Session Initiation Protocol (SIP) 80 -- 5.2.1 SIP Architecture 81 -- 5.2.2 SIP Messages 88 -- 5.2.3 SIP Header Fields and Behaviors 94 -- 5.3 Session Description Protocol 101 -- IN SHORT: ABNF 104 -- 5.4 Media Gateway Control Protocol 107 -- 5.4.1 MGW Functions 107 -- 5.4.2 MGW Connection Model 110 -- 5.4.3 Megaco Procedures 112 -- 5.4.4 Megaco Details 115 -- 5.4.5 Signaling Conversion 119 -- 5.4.6 Voice Transcoding 119 -- 5.5 H.323 120 -- 5.5.1 H.323 Architecture 121 -- 5.5.2 Gatekeeper 123 -- 5.5.3 Gateway 126 -- 5.5.4 Terminal 126 -- 5.5.5 Multipoint Control Unit 127 -- 5.5.6 Call Procedures 128 -- 5.6 Directory Services 134 -- 5.6.1 Domain Name Service (DNS) 134 -- 5.6.2 ENUM 135 -- 6 VoIP and Unified Communications Define the Future 139 -- 6.1 Voice as Before, with Additions 139 -- 6.2 Legacy Services to Keep and Improve with VoIP 140 -- 6.2.1 Flexible Call Routing and 800 Numbers 141 -- 6.2.2 Call on Hold 141 -- 6.2.3 Call Transfer 142 -- 6.2.4 Call Forwarding 142 -- 6.2.5 Audio Conferencing 142 -- 6.2.6 Video Conferencing 143 -- 6.2.7 Local Number Portability 144 -- 6.2.8 Direct Inward Dialing, Dialed Number Indication 144 -- 6.2.9 CallMessage Waiting 145 -- 6.2.10 Call Recording 146 -- 6.2.11 Emergency Calling (E911) 146 -- 6.2.12 Tracking IP Phone Locations for E911 150 -- 6.3 Facsimile Transmission 153 -- 6.3.1 Facsimile on the PSTN 153 -- 6.3.2 Real-Time Fax over IP: Fax Relay or T.38 155 -- 6.3.3 Store-and-Forward Fax Handling 160 -- 6.3.4 IP Faxing over the PSTN 161 -- 6.4 Phone Features Added with VoIPUC 162 -- 6.4.1 Presence 163 -- 6.4.2 Forking 163 -- 6.4.3 Voicemail1/4eMail 163 -- 6.4.4 SMS Integration 164 -- 6.4.5 Instant Messaging 165 -- 6.4.6 Webinar Broadcasts 168 -- 6.4.7 Telepresence 168 -- 6.4.8 More UC Features to Consider 168 -- 7 How VoIP and UC Impact the Network 171.
7.1 Space, Power, and Cooling 171 -- 7.2 Priority for Voice, Video, Fax Packets 172 -- 7.3 Packets per Second 174 -- 7.4 Bandwidth 174 -- 7.5 Security Issues 175 -- 7.5.1 Eavesdropping and vLAN Hopping 176 -- 7.5.2 Access Controls for Users and Connections 176 -- 7.5.3 Modems 177 -- 7.5.4 DNS Cache Poisoning 177 -- IN SHORT: Earliest Instance of DNS Cache Poisoning 179 -- 7.5.5 Toll Fraud 179 -- 7.5.6 Pay-per-Call Scams 179 -- 7.5.7 Vishing 180 -- 7.5.8 SIP ScanningSPIT 180 -- 7.5.9 Opening the Firewall to Incoming Voice 181 -- 7.6 First Migration Steps While Keeping Legacy Equipment 181 -- 7.6.1 Circuit-Switched PBX 182 -- 7.6.2 Digital Phones 182 -- 7.6.3 Analog Phones and FX Service 183 -- 7.6.4 Facsimile Machines 184 -- 7.6.5 Modems 185 -- 8 Interconnections to Global Services 187 -- 8.1 Media Gateways 188 -- 8.2 SIP Trunking 192 -- 8.3 Operating VoIP Across Network Address Translation 196 -- 8.3.1 Failures of SIP, SDP (Signaling) 199 -- 8.3.2 Failures of RTP (Media) 199 -- 8.3.3 Solutions 200 -- 8.3.4 STUN: Session Traversal Utilities for NAT 201 -- 8.3.5 TURN: Traversal Using Relays around NAT 204 -- 8.3.6 ICE: Interactive Connectivity Establishment 206 -- 8.4 Session Border Controller 207 -- 8.4.1 Enterprise SBC 209 -- 8.4.2 Carrier SBC 210 -- 8.5 Supporting Multiple-Carrier Connections 212 -- 8.6 Mobility and Wireless Access 213 -- 8.6.1 VoIP on Wireless LANsWi-Fi 213 -- 8.6.2 Integration of Wi-Fi and Cellular Services 214 -- 8.6.3 Packet Voice on Mobile Broadband: WiMAX, LTE 214 -- 8.6.4 Radio over VoIP 215 -- IN SHORT: E&M Voice Signaling 216 -- 9 Network Management for VoIP and UC 217 -- 9.1 Starting Right 218 -- 9.1.1 Acceptance Testing 219 -- 9.1.2 Configuration Management and Governance 220 -- 9.1.3 Privilege Setting 220 -- 9.2 Continuous Monitoring and Management 221 -- 9.2.1 NMS Software 222 -- 9.2.2 Simple Network Management Protocol 223 -- 9.2.3 Web Interface 224 -- 9.2.4 Server Logging 224 -- 9.2.5 Software Maintenance 225 -- 9.2.6 Quality of ServiceExperience Monitoring 225.
9.2.7 Validate Adjustments and Optimization 226 -- 9.3 Troubleshooting and Repair 226 -- 9.3.1 Methods 226 -- 9.3.2 Software Tools 228 -- 9.3.3 Test Instruments 229 -- 10 Cost Analysis and Payback Calculation 231 -- 11 Examples of Hardware and Software 237 -- 11.1 IP Phones 237 -- 11.2 Gateways 240 -- 11.3 Session Border Controllers 242 -- 11.4 Call-Switching Servers 244 -- 11.4.1 IP PBX 246 -- 11.4.2 Conference BridgesControllers 248 -- 11.4.3 Call Recorder 250 -- 11.5 Hosted VoIPUC Service 251 -- 11.6 Management SystemsWorkstations 252 -- 12 Appendixes 253 -- 12.1 Acronyms and Definitions 253 -- 12.2 Reference Documents 268 -- 12.2.1 RFCs 268 -- 12.2.2 ITU Recommendations 272 -- 12.2.3 Other Sources 272 -- 12.3 Message and Error Codes 274 -- Index 277.
Altri titoli varianti Understanding VoIP and unified communications and the future voice network
Record Nr. UNINA-9910825080303321
Flanagan William A  
Hoboken, N.J., : Wiley, c2012
Materiale a stampa
Lo trovi qui: Univ. Federico II
Opac: Controlla la disponibilità qui