Stp Statistics - ZyXEL Communications GS1900-8 User Manual

Table 45 Monit or > Spanning Tree > MST Port ( cont inued)
LABEL
I ndent ifier ( Priorit y
/ Port I d)
I nt ernal Pat h
Cost ( Operat ion)
Regional Root
Bridge
I nt ernal Root Cost
Designat ed Bridge
Port Role
Port St at e

14.2.5 STP Statistics

( R) STP det ect s and breaks net work loops and provides backup links bet ween swit ches, bridges or
rout ers. I t allows a Swit ch t o int eract wit h ot her ( R) STP- com pliant swit ches in your net work t o
ensure t hat only one pat h exist s bet ween any t wo st at ions on t he net work.
The Swit ch uses I EEE 802.1w RSTP ( Rapid Spanning Tree Prot ocol) t hat allows fast er convergence
of t he spanning t ree t han STP ( while also being backwards com pat ible wit h STP- only aware
bridges) . I n RSTP , t opology change inform at ion is direct ly propagat ed t hroughout t he net work from
t he device t hat generat es t he t opology change. I n STP , a longer delay is required as t he device t hat
causes a t opology change first not ifies t he root bridge and t hen t he root bridge not ifies t he
net work. Bot h RSTP and STP flush unwant ed learned addresses from t he filt ering dat abase. I n
RSTP , t he port st at es are Discarding, Learning, and Forwarding.
Not e: I n t his user 's guide, " STP" refers t o bot h STP and RSTP .
Use t his screen t o view t he Swit ch's spanning t ree STP st at ist ics. Click M onit or > Spa nn in g Tr e e
> STP St a t ist ics t o access t his screen.
Figure 79 Monit or > Spanning Tree > STP St at ist ics
Chapter 14 Monitor: Spanning Tree
DESCRIPTION
This field displays t he ident ifier ( in priorit y / port num ber) .
Pat h cost is t he cost of t ransm it t ing a fram e on t o a LAN t hrough t hat port . I t is
recom m ended t o assign t his value according t o t he speed of t he bridge. The slower t he
m edia, t he higher t he cost .
Root bridge refers t o t he base of t he spanning t ree.
This field displays t he int ernal root cost .
For each LAN segm ent , a designat ed bridge is select ed. This bridge has t he lowest cost
t o t he root am ong t he bridges connect ed t o t he LAN.
This field displays t he st at e of t he port role.
This field displays t he st at e of t he port .
GS1900 Series User's Guide
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