© 2009 Avaya Inc. All rights reserved.1 Chapter Eight, Troubleshooting Module Two – Best Practices

© 2009 Avaya Inc. All rights reserved.2 Best Practices Overview Using a structured approach when troubleshooting IP Office issues will help obtain the information required for resolution more quickly. Identify and quantify symptoms of the issue: – Who: individual, group, everyone – What: hardware, application, feature, performance – When: time, day, frequency, repeatable, call volume – Where: local, remote – How: sequence of events, inbound / outbound calls, number dialed

© 2009 Avaya Inc. All rights reserved.3 Additional Discovery Determine if there is additional documentation to assist in resolving the issue: Network assessment / baseline Network diagrams / schematics / IP address schemes Wiring diagrams IP Office Audit trail System backup procedures – IP Office backup configurations – Voic Pro – Other application servers

© 2009 Avaya Inc. All rights reserved.4 IP Office Knowledgebase For troubleshooting IP Office issues Avaya provides a number of online resources that can be used for assistance. The IP Office Knowledgebase is a central repository for information IP Office including: – Technical Tips, Bulletins and Caveats (known issues) – Product Documentation / documentation corrections – Application Notes for integrating Third Party products

© 2009 Avaya Inc. All rights reserved.5 Avaya Support Web Site In addition to links to IP Office Documentation and software downloads, the Avaya Support web site hosts a searchable knowledgebase called the InSite Knowledgebase. InSite contains articles, job aides and other information useful for troubleshooting IP office issues. Registered users can access on-line services and additional content. (

© 2009 Avaya Inc. All rights reserved.6 Using OSI Model for Troubleshooting The OSI Model (Open System Interconnection) provides a common framework for dividing communications system into logical segments. Methods of using the OSI model: Bottom up – troubleshooting by going from the physical layer (layer 1) up to the application layer (layer 7) Top down - troubleshooting by going from the application layer (layer 7) down to the physical layer (layer 1) Divide and Conquer – in this method, you start with whatever layer you feel is most likely the cause of the problem, then move in whatever direction you feel is the more likely cause of the issue (either up or down the OSI model)

© 2009 Avaya Inc. All rights reserved.7 OSI Fundamentals The segment division can be used to isolate problems. For example, testing each layer, starting from the bottom up makes it possible to isolate problems to a specific layer. Each layer of the OSI Model relies on the layers below it in order to operate.

© 2009 Avaya Inc. All rights reserved.8 Network Assessment A network assessment should include a determination of the following: A network audit to review existing equipment and evaluate its capabilities, including its ability to meet both current and planned voice and data needs. A determination of network objectives, including the dominant traffic type, choice of technologies and setting voice quality objectives. The assessment should leave you confident that the network will have the capacity for the foreseen data and voice traffic, and can support SIP, H323, DHCP, TFTP and jitter buffers in VoIP applications.

© 2009 Avaya Inc. All rights reserved.9 Network Assessment Targets Latency: Less than 180ms for good quality. Less than 80ms for toll quality. Note that the different audio codecs used each impose a fixed delay caused by the codec conversion as follows: G711: 20ms, G723a: 80ms, G729: 40ms Packet Loss: Less than 3% for good quality. Less than 1% for toll quality. Jitter: Less than 20ms Round Trip Delay: Less than 160ms is high quality. Less than 350ms is good quality. Duration: Monitor statistics once every minute for a full week.

© 2009 Avaya Inc. All rights reserved.10 Quality of Service When transporting voice over low speed links it is possible for normal data packets (1500 byte packets) to prevent or delay voice packets (typically 67 or 31 bytes) from getting across the link. It is important that all routers and switches in a network to have some form of Quality of Service mechanism. IP Office supports the DiffServ (RFC2474) QoS mechanism. – This uses a Type of Service (ToS) field in the IP packet header. The IP Office uses this field to prioritize voice and voice signaling packets on its WAN interfaces. Note: This will be only available and supported on IP Office 406V2 and 412 using the WAN connection.

© 2009 Avaya Inc. All rights reserved.11 Escalating IP Office Issues It is essential that all relevant information is documented and collected for escalation. This will save valuable time as the problem is escalated to the appropriate level of support. Items required for escalation of application issues vary based on the application and the specific issue. However, some items are required for ALL escalations, including: – A detailed description of the customer issues including what services are being affected, which user actions, user numbers and user types. – A copy of the IP Office(s) configuration file(s) – The version / release of IP Office software – log files generated by the IP Office System Monitor application – Notes regarding the troubleshooting methods used and results

© 2009 Avaya Inc. All rights reserved.12 Escalating IP Office Application Issues Items required for ALL application escalations, include: Computer information: – CPU Type / speed – Amount of installed memory – Operating System & Service Pack level – Hard Drive capacity and space available – Other applications on the computer IP Office Applications (one-X Portal, ContactStore, etc.) Anti-virus, anti-spam, firewall

© 2009 Avaya Inc. All rights reserved.13 Escalating Voic Issues In addition to the IP Office and server PC information, items required for escalating voic issues include: Voic type and version: – Embedded – Voic Pro Copy of the Voic Pro database (.mdb file) Debug View trace(s) NOTE: While not generally required for escalation purposes, System Status Application Snapshots and Continuous Logs can be very useful in isolating IP Office issues.

© 2009 Avaya Inc. All rights reserved.14 Escalating VoIP / IPO Network Issues Items required for escalating network related issues include: Network assessment / network diagram(s) – Detailed network connectivity information including connection types and bandwidth – IP address scheme of main switches and routers in the network – QoS Settings – VLAN information Make / model and software / firmware versions of IP phones Number of IP phones registered to the IP Office Verify the VCM hardware / licensing A trace using packet capture software (see Technical Tip 195)