From: David Hiers (David_Hiers@adp.com)
Date: Wed Dec 03 2003 - 12:06:41 GMT-3
Start as low as you can. Fiber and gbic first.
Symbol errors can be corrected by the encoding (manchester, in the example provided), so they don't necessarily cause crc errors.
David
********************************************
David Hiers
CCIE, CISSP
ADP Dealer Services
2525 SW First Avenue
Portland, OR 97201
v: 503 402 3703
email: david_hiers@adp.com
********************************************
-----Original Message-----
From: Oliver Ziltener [mailto:ziltener@netcloud.ch]
Sent: Wednesday, December 03, 2003 6:58 AM
To: David Hiers; ccielab@groupstudy.com
Subject: AW: slight offtopic: Cat4000: Interface Symbol-Err?
Hello David
thanks for the feedback.
How I should interpret lots of sysmbol error?
Does that mean my fiber produce failure, or the GBIC is fault, or is more
related to the Switch/Router interface?
Are symbol errors related to other ethernet failure like crc?
thanks
Oliver
-----Urspr|ngliche Nachricht-----
Von: David Hiers [mailto:David_Hiers@adp.com]
Gesendet: Mittwoch, 3. Dezember 2003 15:28
An: ccielab@groupstudy.com
Betreff: RE: slight offtopic: Cat4000: Interface Symbol-Err?
Symbols are pretty low level things. From the IEEE 802.3 2000 spec:
symbol: Within IEEE 802.3, the smallest unit of data transmission on the
medium. Symbols are
unique to the coding system employed. 100BASE-T4 uses ternary symbols;
10BASE-T uses Manchester
symbols; 100BASE-X uses binary symbols or code bits; 100BASE-T2 and
1000BASE-T uses quinary
symbols.
It goes on to be of even more "help":
Manchester encoding is used for the transmission of data across the AUI.
Manchester encoding is a binary
signaling mechanism that combines data and clock into "bit-symbols." Each
bit-symbol is split into two
halves with the second half containing the binary inverse of the first half;
a transition always occurs in the
middle of each bit-symbol. During the first half of the bit-symbol, the
encoded signal is the logical complement
of the bit value being encoded. During the second half of the bit-symbol, the
encoded signal is the
uncomplemented value of the bit being encoded.
David
********************************************
David Hiers
CCIE, CISSP
ADP Dealer Services
2525 SW First Avenue
Portland, OR 97201
v: 503 402 3703
email: david_hiers@adp.com
********************************************
-----Original Message-----
From: Oliver Ziltener [mailto:ziltener@netcloud.ch]
Sent: Wednesday, December 03, 2003 1:24 AM
To: ccielab@groupstudy.com
Subject: slight offtopic: Cat4000: Interface Symbol-Err?
Hello
does anyone knows what is the meaning of Symbol-Err?
I didn't find any good document on the cco!
This is an printout form the cco.
4507#show interfaces GigabitEthernet 1/1 counters errors
Port CrcAlign-Err Dropped-Bad-Pkts Collisions Symbol-Err
Gi1/1 0 0 0 0
Port Undersize Oversize Fragments Jabbers
Gi1/1 0 0 0 0
Port Single-Col Multi-Col Late-Col Excess-Col
Gi1/1 0 0 0 0
Port Deferred-Col False-Car Carri-Sen Sequence-Err
Gi1/1 0 0 0 0
thanks
Oliver
This archive was generated by hypermail 2.1.4 : Sat Jan 03 2004 - 08:25:35 GMT-3