Border profiles for Internet peering

Note

Note

This feature is applicable only for SLX 9640 devices.

Previous releases supported Internet routing tables with limited IPv4 routes after FIB compression and hardware optimization features were enabled. This scale is applicable to Internet routing only on the default VRF.

The FIB compression feature compresses route entries to ensure optimal resource utilization. When there is a more-specific and a less-specific route pointing to a same next-hop, FIB compression addresses the more-specific route and programs only the less-specific route in the hardware.

The hardware optimization feature allows the user to program /24 prefix routes in longest exact match (LEM) table. When this feature is enabled, all /23 routes (split into two /24 routes) and /24 prefix routes are programmed into the LEM table. This feature uses more LEM memory than is required for longest prefix match (LPM), and so can be used on devices that have more LEM than LPM capacity.

External TCAM profiles

SLX 9640 devices support up to 5.7 M IPv4 and 900 K IPv6 internet routes under certain ETCAM profiles when FIB compression is enabled. These profiles can be used at border nodes for Internet peering to support Internet route tables over multiple VRFs.

The following external TCAM (ETCAM) profiles are supported, by means of the profile etcam in hardware configuration mode:
  • Profile ETCAM default: This profile programs IPv4 unicast routes into an external lookup device (ELK), and the internal LPM table is used to program IPv6 unicast routes. This is the default profile in the system.

  • Profile ETCAM IPv6-route: This profile programs IPv6 unicast routes into the ELK, and the internal LPM table is used to program IPv4 unicast routes.
  • Profile ETCAM IPv4-IPv6-route: This profile programs both IPv4 and IPv6 unicast routes in the ELK.
The following table provides values that can be used for network design purposes.
Important

Important

These values are to be viewed as approximate, for design purposes only. They are based on a compression ratio of 30%. The compression ratio is subject to the routes and next-hop combinations that are available in the system, and it may vary from one network design to another. Refer to release notes and scale documentation for further information.
Table 1. Approximate scale support, per profile, for design purposes
ETCAM profile FIB compression disabled FIB compression enabled
IPv4 unicast routes IPv6 unicast routes IPv4 unicast routes IPv6 unicast routes
profile etcam default 4,000,000 256,000 5,700,000 365,000
profile etcam ipv6-route 1,000,000 1,000,000 1,400,000 1,400,000
profile etcam ipv4-ipv6-route 4,000,000 700,000 5,700,000 900,000