Also see: Internet & Network Bandwidth & Monitoring & QOS for a discussion of maximizing bandwidth
Combining Internet Connections for Robust Redundant ConnectivityEdit
One option is to install a Fatpipe Extreme to load balance a connection from various sources (such as Comcast and ATT.) You will end up with the combined connections that will load balance and provide redundancy. Fatpipe can bind different types of connections for redundancy and is worth looking at. You can use round-robin dns with your dns provider (e.g. dnsmadeeasy.com) for your internal website.
Several dual or twin WAN devices exist to effectively combine Internet connections (such as T1, Cable, DSL). Effectively managed, you can load balance between the line so that "x" percent uses the cable Internet and "y" percent uses a T1. Even in load balancing mode, if one connection should fail, the other picks up the drop and your users are none the wiser. There are many different devices available. On the more basic, small scale, Xincom. On more enterprise-level, Barracuda's link balancer.
T1 plus Cable ModemEdit
- We've had a T-1 for a number of years, and this year added a Comcast Business Internet connection at 8/1 w/ static IP for our campus of 300+ PCs. The T-1 is used for incoming traffic (intranet stuff) and outgoing email, the Comcast connection is used for just about everything else. We run an ISA Server, which doesn't support multiple gateways, so we route all of this through a pfSense box (www.pfsense.org) I set up in front of the ISA Server. The pfSense box has the two connections in a fail-over pool, so that if the cable modem goes down, traffic will flow over the T1. I can set up rules that route traffic over different interfaces based on protocol, source ip, dest ip, etc. It works very well for us, and has made a dramatic difference in our access speeds. It gives us the reliability/SLA of a T-1 for critical incoming and outgoing services, yet it also gives us the bandwidth to support media-rich sites for less critical activities, all without breaking the bank. Our T-1 costs us about $500 month after taxes, the Comcast connection is $170, and the pfSense box was around $500 (little 1U server, software is free/open source). All in all, a very cost effective solution. I can't imagine finding something better until business-class FIOS is available in the area. On important note, it was necessary for us to get a static IP on the Comcast connection for our subscription services, so make sure you look into that (it was only $8 month). I'd be happy to offer any other information you're looking for.
- I'm not sure of your market, of course, but our Comcast rep quoted me the following for Staunton: (down/up speeds)
- 8Mbps/1Mbps - $160 per month
- 6Mbps/784kbps - $95 per month
- 4Mbps/384kbps - $60 per month
- We use 2 Comcast 6Mbps lines and they have been very stable. We have 2 data T1's one from XO and one from Speakeasy. The XO T1 has been extremely unreliable. We also have 2 7.1 Mbps Verizon dsl lines and a 1.5 synchronous dsl line (T1 equivalent) from USLEC which have been extremely stable
- It seems that Comcast's service depends on your region and the network they have there. We're in an area with a decent network and have two Comcast Workplace Enhanced lines feeding into our Sonicwall 3060. We've had this setup for over a year and have only lost our connection when a squirrel chewed through the rigid line running down our street. There have been some other minor problems but overall we've been very pleased with their service. At about $160 per line per month the price is incredibly cheaper than what we used to pay for our T1s. The Sonicwall 3060 will do failover and allow you to use two connections but it doesn't do true load balancing. The unit will do round robin and percentage based load sharing but does not actively analyze bandwidth usage and adjust things to balance the load. You should easily be able to combine a T1, Cable connection or DSL together using the Sonicwall. As someone mentioned you can create routes on it to direct traffic to specific lines. Get Comcast to give you a trial period and try the cable line with your T1 connection and the Sonicwall. You won't need any additional equipment other than the cable modem. It's pretty easy to setup and you'll know what you might be getting into.
- I've set up routes on the Sonicwall to port forward specific apps to the cable modem and other apps to the T1.
Multiple ISP Connections for Back-up InternetEdit
We have three DSL connections servicing our campus. They are configured as follows:
Firewall1 -> 1.5Mbps SDSL. Dedicated for our email and WTS traffic. Vendor: SDSL.NET
Firewall2 -> 2 Verizon ADSL 7.1Mbps/768KB links. They are connected to a Hotbrick load balancing router (http://www.hotbrick.com/produto.asp?tipo=2&codPro=55 ) The unit supports up to 8 WAN connections.
We also called Time Warner for a cable modem connection to be added to our pool of WAN connections.
You may also want to look at www.peplink.com. Their load balancing firewall/routers are highly rated. If I had to do it again I would have used Peplink. Lastly, configure the gateway addresses on all you campus computers to point to firewall2 first and then firewall1. This allows for the failure of either firewall or one/more DSL connections and still have Internet connectivity. You might think all this is expensive but we only pay about $500/month for all three connections. Another great benefit of this setup is that it allows all user traffic to be routed through the load balancing router while routing mission critical traffic through the SDSL connection.