VRRP and VRRP-Extended

Besides VRRP not being proprietary, there are a few minor differences between the protocols as well:

• With HSRP, each interface must have an IP address that is separate from the HSRP group address. VRRP lets you share the Master's interface IP address.
• On Cisco devices, VRRP is configured to preempt by default, whereas HSRP is not configured to preempt by default.
• On Cisco devices, HSRP sends hellos every 3 seconds and has a dead timer of 10 seconds. VRRP sends advertisements every 1 second and has a dead timer of roughly three times the advertisement interval.
• VRRP can be configured to learn the timer configuration from the Master.

Same thing, different (older) branding. Normally for 802.1ad there's a C-TAG and an S-TAG. The C-TAG (customer tag) will have almost always have a value of 8100 set in its TPID (tag protocol identifier) field. The S-TAG (service tag - the tag on top) will have a separate set of fields (same as the C-TAG: PCP/DEI/TPID/VID bits) and its TPID should be 0x88a8 by the standard. A lot of vendors will let you set the value for the S-TAG TPID to something arbitrary (Brocade likes to recommend 9100 a lot - probably for compatibility reasons). Some vendors (Brocade also being one of them) will let you also set the C-TAG TPID but I can't think of any useful reason why someone would want to deviate from the norm of 8100. It's more common to want/need to change the S-TAG TPID value.