What do you get when spending $1 million for a single Cisco router?

Cisco List Price $980,000.00 Cisco uBR10012 Universal Broadband Router CMTS Cable Modem Termination System

Brian Wilson - CISSP CCNA CCSE CCAI MCP JNCIA Network+ Security+, email: Slimjim100@slimjim100.com Is the well known author of Slimjim100's Blog - the DOCSIS Engineer Blog (Data Over Cable Service Interface Specifications). Brian has taken time out of his busy schedule to help educate us regarding Cisco's million dollar router - the Cisco uBR10012 Universal Broadband Router.

So what do you get for just over $980,000.00 (list price) when you are an MSO - Multiple Service Operator or cable company and want to service your customer’s data and voice via DOCSIS cable modems?

Brian, who works on a large number of these "Million Dollar Routers" and has deployed many of them in live networks, is offering us the following details.

The Cisco 10k is a fully redundant CMTS - Cable Modem Termination System that supports up to 64,000 subscribers (largest subscriber capacity per CMTS on the market).

But Brian recommends not loading more than 45,000 subscribers when providing both data and voice services to insure not to overload bandwidth and hardware.

With the Cisco 10k you have up to 8 RF DOCSIS 2.0 5x20 line cards.

You may have 8 of the line cards but there is one catch.

One of the line cards is reserved for redundancy or protection if you plan to run the CMTS with HA (High Availability).

Looking at the rear of the Cisco chassis we can see the rear slots for GIG-E line cards, OC-48 line cards, and/or the newer SPA interface processor cards that allow you to support wideband.

Wideband Architecture:

On the front of the 10k are power supplies (your choice of AC or DC power) and the PRE (Processor Routing Engine) cards. PRE cards are the brains of the CMTS and this is where you find PIMICA slots for the IOS and your console ports. You also have 1 fast Ethernet port per PRE, but this port is reserved for communication to the RF switch if you plan on using HA for full redundancy.

The front of the chassis also has a small LCD but so far there has not been any supported functions for the LCD other than displaying the Cisco logo. From what Brian has heard from Cisco, in later releases of IOS software the LCD display will support displaying information about the CMTS. The 10k itself is very large taking up about 18 rack units (RU) and this is just the chassis not including the needed RF switches to support redundancy (they take up 4 RU’s each and you need 2 of them).

So you may now wonder how the command line looks in a Cisco 10k since that thing is the size of half a server rack.

Well it’s the same as any other Cisco router running IOS.

The only real difference from the Cisco uBR (Universal Broadband Router) routers and other Cisco routers is the RF and DOCSIS commands and configuration.

But this is the biggest learning curve you would face if you happen to have to work on a CMTS.

The config on a 10k with 8 line cards is about 80 text pages long with all the cable interface lines, but 90% of it is just repeat commands for the cable interfaces.

Below is a sample of one cable interface config:

!
interface Cable5/0/0
 no ip address
 ip verify unicast reverse-path
 no ip unreachables
 load-interval 30
 cable tftp-enforce mark-only
 cable shared-secret 7 
 cable sync-interval 4
 cable insertion-interval automatic 20 256
 cable bundle 1 master
 cable downstream annex B
 cable downstream modulation 64qam
 cable downstream interleave-depth 32
 cable downstream frequency 659000000
 cable downstream channel-id 0
 no cable downstream rf-shutdown
 cable upstream 0 description 
 cable upstream 0 connector 0
 cable upstream 0 frequency 30704000
 cable upstream 0 power-level 2
 cable upstream 0 power-adjust continue 6
 cable upstream 0 channel-width 3200000
 cable upstream 0 minislot-size 4
 cable upstream 0 range-backoff 3 6
 cable upstream 0 modulation-profile 21
 cable upstream 0 s160-atp-workaround
 no cable upstream 0 shutdown
 cable arp filter request-send 3 2
 cable arp filter reply-accept 1 3
 no cable ip-multicast-echo
 cable dhcp-giaddr primary
 cable helper-address 172.xxx.xxx.xxx
 cable privacy accept-self-signed-certificate
 keepalive 1
 hold-queue 1024 in
! 

Note: This config example is just 1 upstream and one downstream out of 40/downstreams and 160 upstreams.

There are a few vendors that come to mind when talking DOCSIS (Data Over Cable Service Interface Specifications), vendors like Arris, Cisco, Motorola, Bigband as well as a couple of other vendors, but the above are your top 4 players in the DOCSIS arena.

What’s the difference between Cisco’s 10k CMTS and the other vendors CMTS’s.

Well, this is one of those loaded questions because Cisco’s 10k has the capacity of 40 downstreams and 160 upstreams while most of the other vendors CMTS’s support 16 downstream and 64 upstreams.

Perhaps at first look it may seem the other vendors are behind, but in fact they are not.

The other vendors CMTS’s are a lot smaller and when you figure out the cost per port they are about the same.

But how each vendor supports redundancy is very different.

While Cisco depends on external RF switches to protect the line cards, all the other vendors use an internal RF switch.

The internal RF switch is the superior design and in this capacity Cisco is lacking.

There are always pros and cons when picking vendors, but when it comes down to it, you have two basic things to look for when picking a CMTS:

1. Hardware design

2. Software reliability

Brian believes that Cisco wins the software race with the IOS but he feels that the Cisco hardware design is lacking for the HA protection.

Most vendors have an area they can claim to be the best at, so it actually comes down to the requirements of your network.

All of the vendors use a very similar command line and follow the DOCSIS specification so that they are compatible with all DOCSIS devices on the network.

In conclusion, the Cisco Million Dollar Router works just like any other router, but your customer or device count is much larger, so you really need to be extremely careful when working on the router, because one false command could adversely affect tens of thousands of customers and/or devices.

What has been your experience with Cisco's Million Dollar Router?

http://www.BradReese.Com

• Cisco

• LANs / WANs

• Software

• VoIP / Convergence

• Cisco uBR10012 Universal Broadband Router

• CMTS - Cable Modem Termination System