option 1.
========
Trade in the 1600s at central site with a Cisco reseller.
3640 router (this is getting end of life, migration path is to use 3700 router - 3725)
NM-FE-2W - 1 Fast ethernet, 2 WAN slots - 3 numbers.
or use NM-2FE-2W - 2 FE, 2 WAN slots - 3 numbers
WIC-1DSU-T1 - 5 numbers. (this has inbuilt CSU/DSU)
or use the existing WIC on the 1600 along with an external CSU/DSU.
option 2
========
Trade in the 1600s with a Cisco reseller.
PIX 501 at remote sites. - 5 numbers.
PIX outside interface will be connected to DSL modem/router.
PIX 515 with 3DES at central site - to terminate VPN
or a VPN Concentrator 3005 to terminate VPN
or a 3600 router with IPSEC -3DES supported IOS to terminate VPN.
Sankar Nair
UC Solutions Architect
Pacific Northwest | CDW
CCIE Collaboration #17135 Emeritus