Chapter 8 Management Network Connectivity

TCP/IP and OSI Networking

Table 8-11

TARP Timers

 

 

 

 

 

 

 

 

 

 

Default

Range

Timer

 

Description

(seconds)

(seconds)

 

 

 

 

 

E1

 

Waiting for response to TARP Type 1 Request PDU

15

0–3600

 

 

 

 

 

T2

 

Waiting for response to TARP Type 2 Request PDU

25

0–3600

 

 

 

 

 

DS3/E3

 

Waiting for response to address resolution request

40

0–3600

 

 

 

 

 

T4

 

Timer starts when T2 expires (used during error recovery)

20

0–3600

 

 

 

 

 

Table 8-12shows the main TARP processes and the general sequence of events that occurs in each process.

Table 8-12 TARP Processing Flow

Process

General TARP Flow

 

 

 

Find a NET that

1.

TARP checks its TDC for a match. If a match is found, TARP returns the

matches a TID

 

result to the requesting application.

 

2.

If no match is found, a TARP Type 1 PDU is generated and Timer E1 is

 

 

started.

 

3.

If Timer E1 expires before a match if found, a Type 2 PDU is generated and

 

 

Timer T2 is started.

 

4.

If Timer T2 expires before a match is found, Timer T4 is started.

 

5.

If Timer T4 expires before a match is found, a Type 2 PDU is generated and

 

 

Timer T2 is started.

 

 

Find a TID that

A Type 5 PDU is generated. Timer DS3/E3 is used. However, if the timer

matches a NET

expires, no error recovery procedure occurs, and a status message is provided to

 

indicate that the TID cannot be found.

 

 

Send a notification

TARP generates a Type 4 PDU in which the tar-ttg field contains the NE’s TID

of TID or protocol

value that existed prior to the change of TID or protocol address. Confirmation

address change

that other NEs successfully received the address change is not sent.

 

 

 

8.6.5.2 TARP Loop Detection Buffer

The TARP loop detection buffer (LDB) can be enabled to prevent duplicate TARP PDUs from entering the TDC. When a TARP Type 1, 2, or 4 PDU arrives, TARP checks its LDB for the NET address of the PDU originator match. If no match is found, TARP processes the PDU and assigns a tar-por, tar-seq (sequence) entry for the PDU to the LDB. If the tar-seq is zero, a timer associated with the LDB entry is started using the provisionable LDB entry timer on the node view OSI > TARP > Config tab. If a match exists, the tar-seq is compared to the LDB entry. If the tar-seq is not zero and is less than or equal to the LDB entry, the PDU is discarded. If the tar-seq is greater than the LDB entry, the PDU is processed and the tar-seq field in the LDB entry is updated with the new value. The Cisco ONS 15310-MA SDH LDB holds approximately 500 entries. The LDB is flushed periodically based on the time set in the LDB Flush timer on the node view OSI > TARP > Config tabs.

Cisco ONS 15310-MA SDH Reference Manual, Release 9.1 and Release 9.2

 

78-19417-01

8-31

 

 

 

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Cisco Systems 15310-MA Tarp Loop Detection Buffer, Default Range Timer Description Seconds, Process General Tarp Flow
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15310-MA specifications

Cisco Systems has established itself as a leader in the networking domain, offering a wide array of solutions to meet the needs of modern businesses. Among its impressive product lineup are the Cisco 15310-CL and 15310-MA routers, designed to provide advanced network performance and reliability.

The Cisco 15310-CL is a versatile platform that primarily serves as a carrier-class router aimed at supporting high-speed data and voice services. It is built to handle the demands of large enterprises and service providers, offering a robust design that ensures maximum uptime and performance. One of its standout features is its modular architecture, which enables users to customize their configurations based on specific application needs. This scalability allows for future expansion without the need for a complete hardware overhaul.

Key technologies integrated into the Cisco 15310-CL include high-density Ethernet interfaces and a comprehensive suite of Layer 2 and Layer 3 protocol support. The device is capable of supporting multiple types of connections, including TDM, ATM, and Ethernet. This flexibility makes it an ideal choice for organizations that require seamless migration between various service types. Moreover, with features such as MPLS (Multiprotocol Label Switching) support and advanced Quality of Service (QoS) mechanisms, the router ensures that critical applications receive the necessary bandwidth and low latency required for optimal performance.

In contrast, the Cisco 15310-MA focuses on access solutions, providing a cost-effective entry point for businesses looking to enhance their network capabilities. It is well-suited for smaller offices or branch locations that need reliable connectivity without the expense and complexity associated with larger systems. The device supports a range of access methods and provides essential features like firewall capabilities, VPN support, and comprehensive security measures to protect sensitive data.

Both models benefit from Cisco's commitment to security and manageability, offering features like enhanced encryption protocols and user authentication mechanisms that help safeguard networks against threats. Additionally, they can be managed through Cisco’s intuitive software tools, simplifying configuration and monitoring tasks for IT administrators.

The Cisco 15310-CL and 15310-MA are ideal solutions for businesses seeking to enhance their network infrastructure, ensuring firms can keep pace with evolving technology demands while maintaining a focus on security and performance. Their combination of advanced features, modular capabilities, and robust support makes them valuable assets in the networking landscape.
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