Tech Guide: ASR 1000s Simplified | Resources | Curvature
New Ask the Expert Video: Hyperconverged Infrastructure and the Nutanix Portfolio
Watch our discussion on HCI and Nutanix by clicking here now.

Tech Guides

Tech Guide: ASR 1000s Simplified

Doing more with less is the primary goal of the ASR 1000 Series Routers, made especially for businesses looking to scale and consolidate data centers and devices. With the firewall, deep-packet inspection, and session border control capabilities built into the ASR box itself, this router offers a wealth of capabilities without requiring additional hardware.

It’s not uncommon to get overwhelmed with all the options that the ASR has to offer. Ultimately, it’s important to understand what’s right for your network. That’s why we teamed up with expert engineers to detail the ASR’s three components, chassis capacity, and fixed hardware and help you decide for yourself.

The ASR 1000 is Cisco’s mid-range router line, capable of anywhere from 2.5Gbps to 100Gbps of throughput, depending on model and installed cards. The platform is targeted towards applications such as BGP border router, broadband aggregation, IPSec aggregation, large-scale NAT gateway, or high-capacity session border controller. The ASR 1000 provides a hardware forwarding engine to ensure consistent throughput regardless of the system’s configuration.


The ASR 1000 line consists of a variety of chassis — some with fixed components like the ASR 1001, ASR 1002 and ASR 1002-X — while other systems are fully modular, like the ASR 1004, 1006, and 1013. The chassis capacity and fixed hardware is detailed in simplicity here:

ASR 1001
ASR 1002
ASR 1002-X
ASR 1004
ASR 1006
ASR 1013
1 SPA card slot 3 SPA card slots 3 SPA card slots 1x RP slot 2x RP slots 2x RP slots
4x SFP slots onboard 4x SFP slots onboard 6x SFP slots onboard 1x ESP slot 2x ESP slots 2x ESP slots
Integrated RP2 Integrated RP1 Integrated RP2 2x SIP card slots 3x SIP card slots 6x SIP card slots
Integrated SIP10 Integrated SIP40 Option of RP1 or RP2 Option of RP1 or RP2 Can take an RP2
Fixed ESP (2.5Gbps base, license upgradeable to 5Gbps) Option of ESP5 or ESP10 Fixed ESP (5Gbps base, license upgradeable to 10, 20 or 36Gbps) Option of ESP10, ESP20 or ESP40 Option of ESP10, ESP20, ESP40 or ESP100 Option of ESP40 or ESP100

Route Processor (RP)

The ASR 1000 route processor is the component of the router that runs the IOS, manages the system, and performs all control plane functions (such as setting up VPN tunnels, initiating SIP sessions, and running the routing protocols).

Currently, two RP models are available, with the RP1 supporting up to 4GB of memory and the RP2 supporting up to 16GB of memory. For high availability and in-service software updating, the ASR 1000 RP is capable (with appropriate licensing) of running two IOS images in an active/standby arrangement, and due to this, only half the installed memory is available to the running IOS image.

Embedded Services Processor (ESP)

The ESP card is the forwarding engine of the ASR 1000—the RP constructs the forwarding table, which is then sent to the ESP, which performs all forwarding, encryption, and other packet manipulation. ASR 1000 ESPs are available in throughputs ranging from 2.5Gbps to 100Gbps of throughput. Note that using the ESP40 or ESP100 requires the use of an RP2.

SPA Cards and Carriers

The ASR 1000 uses SPA cards exclusively for interfaces. While smaller chassis like the ASR 1001 and ASR 1002 present SPA card slots, larger systems like the ASR 1004 and up require the use of an ASR 1000 SIP carrier card to provide SPA card slots. There are two SIP card models available: the SIP10 (up to 10Gbps of throughput) and the SIP40 (40Gbps of throughput).

When using these SIP cards, be aware of these restrictions:
  • The SIP10 can be oversubscribed up to 2:1; any further oversubscription will result in SPA cards being shut down by the system.
  • As the SIP40 provides 40Gbps of throughput, and the fastest SPA card is a 1 port 10GbE card, there is no way to oversubscribe the SIP40 at this time.


Twitter Facebook LinkedIn Instagram Youtube
2810 Coliseum Centre Drive Suite 600 28217 Charlotte, NC
+1(704)921-1620 [email protected]