NO! here's why.
Start with the basics of routing. When you get your first ISP connection, two things happen:
a) you get TCP settings and
b) a route table is created
Look at the TCP settings and then the Route table:
TCP Settings:
Code:
Ethernet adapter Local Area Connection:
Connection-specific DNS Suffix . : rr.com
Description . . . . . . . . . . . : Realtek RTL8139/810x Family Fast Ethernet NIC
Physical Address. . . . . . . . . : 00-aa-bb-cc-dd-ee
Dhcp Enabled. . . . . . . . . . . : Yes
Autoconfiguration Enabled . . . . : Yes
IP Address. . . . . . . . . . . . : 192.168.0.4
Subnet Mask . . . . . . . . . . . : 255.255.255.0
[b] Default Gateway . . . . . . . . . : 192.168.0.1 << DEFAULT[/b]
DHCP Server . . . . . . . . . . . : 192.168.0.1
DNS Servers . . . . . . . . . . . : 209.18.47.61
209.18.47.62
Lease Obtained. . . . . . . . . . : Friday, September 30, 2011 8:03:27 PM
Lease Expires . . . . . . . . . . : Monday, January 18, 2038 8:14:07 PM
Route Table:
Code:
C:\Documents and Settings\Jeff>[b]route print[/b]
===========================================================================
Interface List
0x1 ........................... MS TCP Loopback interface
0x2 ...00 0f b0 3d bc 1d ...... Realtek RTL8139 Family PCI Fast Ethernet NIC - Packet Scheduler Miniport
0x10004 ...00 02 72 1f 4a 81 ...... Bluetooth Device (Personal Area Network)
================================================================
Active Routes:
Network Destination Netmask Gateway Interface Metric
[B] [COLOR="Red"]0.0.0.0[/COLOR] 0.0.0.0 192.168.0.1 192.168.0.4 20[/B]
127.0.0.0 255.0.0.0 127.0.0.1 127.0.0.1 1
192.168.0.0 255.255.255.0 192.168.0.4 192.168.0.4 20
192.168.0.4 255.255.255.255 127.0.0.1 127.0.0.1 20
192.168.0.255 255.255.255.255 192.168.0.4 192.168.0.4 20
224.0.0.0 240.0.0.0 192.168.0.4 192.168.0.4 20
255.255.255.255 255.255.255.255 192.168.0.4 192.168.0.4 1
255.255.255.255 255.255.255.255 192.168.0.4 10004 1
[B]Default Gateway: 192.168.0.1[/B]
================================================================
The TCP setting tells you where the gateway is located and that is confirmed in the
Routing Table as the
Default Gateway: 192.168.0.1 entry.
Notice that the Network Destination is show as
0.0.0.0
This means, if all else fails (aka, don't know where to send packets), send it here.
Now as you add more NIC cards (or routers with other ISP connections), your system
still has ONLY one default route. All that extra effort doesn't change the routing table
and all your ethernet traffic STILL exit your system headed for the Default Route.
Conclusion: You can not get extra "bandwidth" by adding more ISP connections.