CISCO1921 to replace the very popular 1841

CISCO1921 is sleek and fast - but do you really need it?

The new CISCO1921 is a replacement for the very popular 1841 .  New licensing and software, (probably) better performance, support for new modules  – it dominates the 1841 and previous generations of branch office routers. 

The current standard, the CISCO1841

1RU, 19 inch rackmountable, single power supply, 256 MB DRAM and 64 MB internal flash.

75,000 PPS (35Mbps w/ 64 byte packet size) performance

2x Fast Ethernet (10/100) ports (RJ45)

2x HWIC slots (but only one FE or GE HWIC may be used at a time)

The 1841 has an integrated VPN processor for IPSec VPN and the option to add an AIM card for SSL VPN capabilites, but the 1841 has no voice capabilities – it is not suitable for voice gateway or call manager applications. However, if you have a SIP trunk or other VoIP data connection, the 1841 does support passing VoIP packets through, as well as very robust QoS to prioritize the VoIP traffic.

Datasheet: http://www.cisco.com/en/US/prod/collateral/routers/ps5853/product_data_sheet0900aecd8016a59b.pdf

The next generation, the CISCO1921

1 RU, 19 inch rackmountable, single power supply, 512 MB DRAM, 256 MB internal flash

15MBPS quoted performance “with services enabled”, likely much faster straight throughput

2x 10/100/1000 ethernet ports (RJ45)

2 EHWIC slots

The 1921 has integrated IPSec and SSL VPN support with upgraded software, but like the 1841, the 1921 cannot be used as a Call Manager or voice gateway (but can still pass VoIP packets through).

Datasheet:

http://www.cisco.com/en/US/prod/collateral/voicesw/ps6789/ps7290/ps10589/data_sheet_c78-598389.pdf

New and simplified software

The new routers now use license keys and a universal image to determine the available features, in the same manner as a PIX or ASA.  This new licensing scheme also has the benefit of producing a clear division between the version of IOS installed and the featureset installed, so you can update the IOS version without touching the featureset part, or upgrade the featureset on a router without touching the IOS file.

In addition, the licensing structure has been further streamlined, now leaving us with just 3 featuresets, none of which overlap.  Here are the contents of each available feature package:

IP Base:  The default featureset; has support for common routing protocols (RIP, OSPF, EIGRP, BGP), common WAN technologies (MLPPP, MLFR), and common LAN technologies (802.1q trunking).  No VPN, firewall, or voice features are present. 

Data: The Data license adds support for MPLS, ATM, IS-IS, and non-IP L3 protocols. 

Security: The Security featureset adds IPSec VPN capabilities, SSL VPN capabilities, and IOS firewall features.

You can apply any combination of these featuresets to the router; you are not restricted to a single featureset per device.

The 1921 also has a much-improved system architecture, with the EHWIC slots now having a high-throughput point to point connection, vs. the old bus-based architecture of the previous routers. 

So the 1921 is a fantastic device, but with similar limitations to its predecessors - it has only a single power supply and no featureset for voice.  Perhaps the biggest question is the following:  At a prospective list price around that of the 1841 ($1300 or $1400 – it doesn’t appear to be on the GPL yet)it will cost roughly 50% more than an 1841 on the open market as they are widely available, and 3x more than a CISCO2611XM or similar device, and either of those will run a network connected to a couple T1’s or a 10mbps Ethernet connection as well as the 1921.  For those that really need the last degree of performance, however, and can live with its limitations it is a good evolutionary step forward from previous generations of small routers.

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