STP and RSTP congergence time
Bookmark this page:
 Yahoo!
 Google
 Windows Live
 del.icio.us
 digg
 Netscape
|
|
||||||||||||||||||||||||||||||||||
|
Posted by on May 9, 2008, 12:10 pm
Please log in for more thread options 1. init (power up) to stable STP is 20+15+15=50s how about RSTP? 2. Topology change STP =30-50s? RSTP? TIA, st | ||||||||||||||||||||||||||||||||||
|
Posted by Albert Manfredi on May 9, 2008, 3:30 pm
Please log in for more thread options In my experience, RSTP can be from around 1 second down to less than 50 msec. It all depends on what broke in the network. Bert | ||||||||||||||||||||||||||||||||||
|
Posted by on May 9, 2008, 4:01 pm
Please log in for more thread options On 5=D4=C29=C8=D5, =CF=C2=CE=E712=CA=B130=B7=D6, Albert Manfredi <bert22...@=
hotmail.com> wrote:
> On May 9, 12:10 pm, aaabb...@hotmail.com wrote: > > > How faster is RSTP than STP? (same topology)
> > 1. init (power up) to stable > > STP is 20+15+15=3D50s > > how about RSTP? > > 2. Topology change > > STP =3D30-50s? > > RSTP? >
> In my experience, RSTP can be from around 1 second down to less than > 50 msec. It all depends on what broke in the network. > > Bert Thanks, The port to change stage is not depends on hello package. right? For RSTP it has alternate port and backup port. The alternate port I can think it is blocking port in STP in another switch. How about buckup port, does it need to be config manually? | ||||||||||||||||||||||||||||||||||
|
Posted by Albert Manfredi on May 9, 2008, 6:27 pm
Please log in for more thread options On May 9, 4:01=A0pm, aaabb...@hotmail.com wrote:
> > In my experience, RSTP can be from around 1 second down to less than
> > 50 msec. It all depends on what broke in the network. > Thanks,
> The port to change stage is not depends on hello package. right? > For RSTP it has alternate port and backup port. The alternate port > I can think it is blocking port in STP in another switch. How about > buckup > port, does it need to be config manually? The alternate and/or backup links are computed automatically. To detect a failed link, you don't use hello packets, but rather the MAC_Operational parameter, which in turn is set according to each specific LAN type. The reason failure detection can be so fast is that in modern LANs, the active or backup/alternate link should never be quiescent, even when idle, so if an alternate path is available, it can be activated very quickly. This is in IEEE 802.1D, Clause 17, which then refers to other clauses in the same Standard. Bert | ||||||||||||||||||||||||||||||||||
|
Posted by on May 9, 2008, 8:15 pm
Please log in for more thread options On 5=D4=C29=C8=D5, =CF=C2=CE=E73=CA=B127=B7=D6, Albert Manfredi <bert22...@h=
otmail.com> wrote:
> On May 9, 4:01 pm, aaabb...@hotmail.com wrote: > > > > In my experience, RSTP can be from around 1 second down to less than
> > > 50 msec. It all depends on what broke in the network. > > Thanks,
> > The port to change stage is not depends on hello package. right? > > For RSTP it has alternate port and backup port. The alternate port > > I can think it is blocking port in STP in another switch. How about > > buckup > > port, does it need to be config manually? >
> The alternate and/or backup links are computed automatically. To > detect a failed link, you don't use hello packets, but rather the > MAC_Operational parameter, which in turn is set according to each > specific LAN type. The reason failure detection can be so fast is that > in modern LANs, the active or backup/alternate link should never be > quiescent, even when idle, so if an alternate path is available, it > can be activated very quickly. > > This is in IEEE 802.1D, Clause 17, which then refers to other clauses > in the same Standard. > > Bert Thanks, I am trying to understand your "words" For backup port, assume there are multiple ports on the same segement, before topology change, Does the backup port automatically random selected? after the active port down, the backup port immediately become active port. I think it shouls impact whole tree. | ||||||||||||||||||||||||||||||||||
| Similar Threads | Posted |
| STP and RSTP congergence time | May 9, 2008, 12:10 pm |
| STP-RSTP query | October 16, 2008, 3:29 am |
| RSTP timing parameters | June 2, 2005, 2:32 pm |
| Topology change in RSTP | May 15, 2006, 4:08 am |
| RSTP - Changing Forward Delay | July 15, 2008, 11:00 am |
| How is a break/reconfiguration propagated in an RSTP network? | December 15, 2005, 7:19 am |
| Link Up Time | March 14, 2006, 12:24 pm |
| Network Time (Newbie Q) | October 19, 2004, 10:45 am |
| LAN cabling : The right time for beginning | February 1, 2006, 5:24 am |
| Why 96 bits of silent time? | November 21, 2006, 8:21 am |
| Ethernet auto-negotiate time | September 11, 2004, 10:19 pm |
| Why CSMA/CD is not suitable for real time applications?? | January 18, 2005, 4:06 am |
| Re: Why CSMA/CD is not suitable for real time applications?? | January 22, 2005, 4:49 pm |
| Shortest ethernet frame time = 5.76uS? | September 9, 2008, 4:55 pm |
| Maximum Auto-Negotiation Time on Twisted-Pair Gigabit Ethernet | June 19, 2008, 8:21 am |
> 1. init (power up) to stable
> =A0 =A0 STP is 20+15+15=3D50s
> =A0 =A0 how about RSTP?
> 2. Topology change
> =A0 =A0STP =3D30-50s?
> =A0 =A0RSTP?