Yes, they should be able to communicate. The switch hardware (fabric / ASIC / whatever) basically needs to de-encapsulate the packet as it is going through anyway, to see what VLAN it is in, check VACLs, etc. Remember that, even with the same encapsulation, a switch can tag packets with different COS/DSCP values, etc, as they go through the switch.
Fred Reimer - CCNA Eclipsys Corporation, 200 Ashford Center North, Atlanta, GA 30338 Phone: 404-847-5177 Cell: 770-490-3071 Pager: 888-260-2050 NOTICE; This email contains confidential or proprietary information which may be legally privileged. It is intended only for the named recipient(s). If an addressing or transmission error has misdirected the email, please notify the author by replying to this message. If you are not the named recipient, you are not authorized to use, disclose, distribute, copy, print or rely on this email, and should immediately delete it from your computer. -----Original Message----- From: dj [mailto:[EMAIL PROTECTED] Sent: Tuesday, August 05, 2003 1:15 PM To: [EMAIL PROTECTED] Subject: Re: Can 802.1q & isl co-exist on same network?? [7:73511] So I assume that vlan info will propagate correctly across both the 802.1q and ISL trunks as follows: 3524 ---- PCa in Vlan 3 | | 802.1q trunk | 3508 | | ISL trunk | 3524 ---- PCb in Vlan 3 Can PCa reach PCb ??? "Reimer, Fred" wrote: > You can mix and match on different ports in the same switch. But obviously > the two ports that are connected together would have to use the same > encapsulation. > > Fred Reimer - CCNA > > Eclipsys Corporation, 200 Ashford Center North, Atlanta, GA 30338 > Phone: 404-847-5177 Cell: 770-490-3071 Pager: 888-260-2050 > > NOTICE; This email contains confidential or proprietary information which > may be legally privileged. It is intended only for the named recipient(s). > If an addressing or transmission error has misdirected the email, please > notify the author by replying to this message. If you are not the named > recipient, you are not authorized to use, disclose, distribute, copy, print > or rely on this email, and should immediately delete it from your computer. > > -----Original Message----- > From: dj [mailto:[EMAIL PROTECTED] > Sent: Tuesday, August 05, 2003 8:43 AM > To: [EMAIL PROTECTED] > Subject: Can 802.1q & isl co-exist on same network?? [7:73511] > > Have a production campus LAN network primarily running with 3508Gs and > 3524XL data switches with gigabit fiber uplinks. All switches are > currently running ISL Vlan trunking between the uplink ports. There's > also a 2620 router running ISL fastethernet subinterfaces configured > with encapsulation ISL. > > I have some non-cisco network devices that only support 802.1q vlan > trunking. I already know the 802.1q trunking on non-cisco equipment > works ok with cisco devices running 802.1q trunking. > > However, when I deploy the non-cisco equipment in the production campus > LAN, can I have some trunk ports running 802.1q trunking and other trunk > ports running ISL. Bottom line: Can ISL and 802.1q co-exist or do I > have to migrate entire LAN to 802.1q vlan trunking?? > > regards, > dj > **Please support GroupStudy by purchasing from the GroupStudy Store: > http://shop.groupstudy.com > FAQ, list archives, and subscription info: > http://www.groupstudy.com/list/cisco.html > **Please support GroupStudy by purchasing from the GroupStudy Store: > http://shop.groupstudy.com > FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html **Please support GroupStudy by purchasing from the GroupStudy Store: http://shop.groupstudy.com FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=73551&t=73511 -------------------------------------------------- **Please support GroupStudy by purchasing from the GroupStudy Store: http://shop.groupstudy.com FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html
