Hi Guys i hv 2 routers connected via an HDLC link A ---- HDLC ----- B A has IOS m Software Version 12.1(6)E2, EARLY DEPLOYMENT RELEASE B has IOS 12.2(1r)XE1, RELEASE SOFTWARE (fc1) Will a regular stac comprssion on the HDLC link work .. i read on the Cisco site (Compression FAQ) saying that IOS versions on both ends of the Link should match any advices.. Knms