QoS

DIFFSERV

IETF RFCs 2474 and 2475 define “services” basically as different ways to treat a network’s different traffic subsets at the Internet Protocol (IP) layer, Layer 3. For example, some packets might be routed to expedite delivery and minimize delay, with other packets routed to minimize loss or cost. Redefining an octet in the Layer 3 headers for IP versions 4, or IPv4 and 6, or IPv6 provides the differentiation between these services (Differentiated Services). IPv4 calls this octet a Type of Service (TOS) octet while IPv6 calls this octet a Traffic Class. In both cases, the octet is interpreted differently than it was originally defined. With Differentiated Services, bits 0 through 5 of the octet identify a Differentiated Services Code Point (DSCP). The DSCP identifies a procedure to be used to handle that packet on a per-hop basis. Bits 6 and 7 of the octet are currently unused, and DSCP-compliant routers ignore them.

With DiffServ, the default DSCP is all zeroes, and represents “no special handling.” RFC 2474 also defines eight “Class Selector Codepoints,” which are the eight DSCP encodings that can be represented by xxx000, where “x” represents one bit. These Code Selector Codepoints are considered prioritized, with the larger numeric values having a higher relative order. DSCP-compliant routers should give the associated packets of larger-valued DSCPs a “probability of timely forwarding” greater than a packet with a lower-valued DSCP. In addition to the eight Class Selector Codepoints, a network can define its own DSCPs by defining encodings that do not terminate in 000. The specific treatment intended by these custom DSCPs will not necessarily be carried out by routers outside the customer’s own network.

The 4600 Series IP Telephone Installation Guide describes the Local Administrative Option for QoS. This option allows you to specify Diffserv values for Layer 3 audio (“L3QAUD”) and signaling traffic (“L3QSIG”) on a telephone-by-telephone basis.

The Avaya H.323 IP Telephones’ DiffServ values change to the values administered on the media server as soon as the telephone registers. For more information, see the document titled Administration for Network Connectivity (555-233-504). Unless there is a specific need in your enterprise LAN, we do not recommend you change the default values.

UDP Port Selection (H.323 Only)

Some data networks include equipment that can perform UDP port selection. This is a mechanism that gives packets with port numbers in a given range priority over packets with port numbers outside that range.

To support UDP port selection, the 4600 Series IP Telephones can be administered from the Avaya Communication Manager Network Region form. Locate specific implementation details for local administration of MCPORT in the 4600 Series IP Telephone Installation Guide. For Avaya Communication Manager administration, find implementation details in Administration for Network Connectivity for Avaya Communication Manager Software. In summary, the system value MCPORT represents the port on the TN2302AP board. Use this port number to administer routers, etc. supporting UDP port selection, to maximize priority of voice packets being exchanged between the PBX and the telephone.

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4600 specifications

The Avaya 4600 series is a line of IP telephones designed for enterprise communication. Known for its robust features and reliability, the 4600 series has been widely adopted in various business environments, from small companies to large corporations.

One of the standout features of the Avaya 4600 series is its support for Voice over Internet Protocol (VoIP). This enables businesses to make voice calls over the internet, which can significantly reduce telecommunications costs. The integration of VoIP technology also allows for seamless communication across different locations, making it ideal for businesses with multiple branches or remote employees.

The design of the Avaya 4600 series phones is user-friendly, featuring a clear display and an intuitive interface. Users can easily navigate through various options, making calls, accessing voicemail, and managing contacts a straightforward task. Many models in the series include customizable soft keys, which allow individuals to tailor the phone's functions to their specific needs. This flexibility is crucial in environments where employees need to quickly adjust their communications settings.

Another key characteristic is the high-quality audio. The Avaya 4600 series incorporates advanced audio technologies that ensure clear and crisp sound quality during calls. This is essential for effective communication, particularly in large meetings or conference calls where clarity is vital.

The Avaya 4600 series also supports various network protocols, including Session Initiation Protocol (SIP), providing compatibility with a wide range of network infrastructures and allowing organizations to choose the system that best fits their needs. This versatility makes the 4600 series an appealing choice for businesses looking to future-proof their communication systems.

Security is a major consideration in any enterprise communication solution, and Avaya has incorporated features in the 4600 series to protect against unauthorized access and cyber threats. Encryption protocols help safeguard call data, ensuring that sensitive business information remains secure.

In terms of deployment, the Avaya 4600 series can be easily integrated into existing networks, as well as managed remotely, which simplifies the installation and maintenance process. This feature is particularly beneficial for large enterprises that require scalability across multiple locations.

Overall, the Avaya 4600 series combines advanced technology, user-friendly design, and comprehensive security measures to provide a reliable and effective communication solution for businesses. As enterprises continue to adapt to a rapidly changing communication landscape, the Avaya 4600 series remains a strong contender for organizations seeking to enhance their telecommunications infrastructure.
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