Using 2 ISP Connections... 1 for UL and 1 for DL?

[spiglia]

I am currently using a 3Mb connection(Bonded T1's) and this is not sufficent enough for the traffic I produce. I am attempting to purchase a comcast 12Mb cable modem connection to use with this T1 service. I would like to use the Cable modem as Download and the 3Mb as upload. I do all routing from a Cisco 3550. has anyone attempted something similar?

Thanks!

 

[Minue]

Hello
To clarify,when you say "upload"do you mean you want the 3Mb connection to upload for your

http://WWW and

FTP servers. And the 12Mb for browsing the Web?
Regards

 

[spiglia]

Minue,

Thanks for your post.... That is correct. I would like to use the 12Mb for browsing and the 3 for any uploading.

 

[eclidad]

We use an 1841 for a similar setup. We have 2 ISPs and 2 blocks of public addresses. Unless I'm missing something it's pretty straight forward.

Our servers sit on addresses from ISP-1. Anything coming to them gets routed from the Serial port (it's a T1) to the vlan on the WIC. Any traffic that originates on the WIC already has a public IP address and is routed to the T1.

Any traffic that originates on internal network gets natted to an address from ISP-2. These get sent to fastethernet0/1 which is connected to our cable modem.

This may not be the best way but it works.

set up route for internally generated traffic:

ip route 0.0.0.0 0.0.0.0 aaa.bbb.ccc.ddd


Vlan2 is the wic with our public servers:

interface Vlan2
ip address xxx.yyy.zzz.241 255.255.255.240
ip access-group 140 in
ip nat outside
ip virtual-reassembly
ip policy route-map Vlan2_Map

route-map Vlan2_Map permit 10
match ip address 103
set default interface Serial0/0/0

access-list 103 remark This list is applied to the Vlan2 route map
access-list 103 remark to force routing of packets from vlan2 to internet
access-list 103 deny ip xxx.yyy.zzz.240 0.0.0.15 209.137.163.240 0.0.0.15
access-list 103 permit ip xxx.yyy.zzz.240 0.0.0.15 any

I hope you find this useful.
- Joel

 

[jneiberger]

The tricky part is this: all traffic is two-way, whether it's upload or download traffic. If you're using TCP, you have to have valid bidirectional paths. You can't split a single TCP session over two links if the links use different addressing. This could be a really messy setup depending on how you do it.

If you need certain devices to always use one link instead of the other, that's fairly easy. If you need the same devices to use different links depending on the type of traffic, that's much more problematic.

 

[spiglia]

Thanks Joel .. i will give this a try!