Overview of the Routing Matrix with a TX Matrix Router

The routing matrix with a TX Matrix router is the first multichassis product from Juniper Networks. The T640 and T320 routers were the first core routers that provided scalable bandwidth and intelligent networking features with a capacity of 80 to 640 gigabits per second (Gbps) of throughput. A key part of the T Series design was the ability to scale individual T640 routers to 2.5 terabits of bandwidth by combining them in a multichassis configuration. Such scalability is now available with the routing matrix.

The physical system of a routing matrix consists of one TX Matrix router and from one to four T640 routers, as shown in Figure 1. A key element of the routing matrix design is the ability to migrate existing T640 routers and connect them with the TX Matrix router through fiber-optic cables and Switch Interface Boards (SIBs).

Figure 1: Routing Matrix with a TX Matrix Router Architecture

The TX Matrix router connection between the T640 routers uses a scalable, three-stage switch fabric. This system architecture provides terabit bandwidth expansion capacity and eliminates the use of subscriber line cards to connect devices within points of presence (POPs). As a result, the primary application for the routing matrix is to collapse aggregation and core layers in large POPs and central offices.

The routing matrix appears as a single router to the operator and utilizes the existing Junos OS command-line interface (CLI) for configuration and management. To manage this multichassis system, some enhancements have been made to the CLI that allow you to select the amount of output you wish to receive when you issue operational commands. You can specify the entire routing matrix, the TX Matrix router, a specific T640 router and its Flexible PIC Concentrators (FPCs), or a combination thereof.

Similarly, you can limit which portions of the routing matrix are modified during configuration or maintenance procedures (for example, performing software upgrades or halting Routing Engines).

Identifying Routing Matrix with a TX Matrix Router Components

• TX Matrix router—

  There is only one TX Matrix router per routing matrix. It is referred to as the switch-card chassis (scc) in the Junos OS CLI.

• T640 routers—

  There can be one to four T640 routers in a routing matrix. These are referred to as line-card chassis 0 through 3 (lcc0–lcc3) in the Junos OS CLI. The T640 router number is set by the hardware. See the TX Matrix Router Hardware Guide for further information on installing and connecting the hardware.

Viewing the Routing Matrix with a TX Matrix Router as a Single Router

Even though a routing matrix with a TX Matrix router can be comprised of five separate physical components (a TX Matrix router and up to four T640 routers), it is best if you consider a routing matrix as a single router. When you issue configuration and operational commands on the TX Matrix router, your view of the routing matrix shows a single routing device with a high number of FPCs and PICs. For a detailed discussion of FPC numbering in a routing matrix with a TX Matrix router, see Adjusting the Configuration to Accommodate Increased FPC Numbers in a Routing Matrix with a TX Matrix Router.