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Re: Wireless STM-1 link


From: Brian Reichert <reichert () numachi com>
Date: Thu, 10 Sep 2009 10:12:03 -0400

On Thu, Sep 10, 2009 at 11:55:40AM +0200, Rens wrote:
All the interfaces are forced to 1Gbps and full duplex.

I thought that with 1000T, you need to keep autonegotiation in place:

  http://etherealmind.com/2008/07/15/ethernet-autonegotiation-works-why-how-standard-should-be-set/

    "A major problem is that many people are also hard setting
    Gigabit Ethernet , and this is causing major problems. Gigabit
    Ethernet must have auto-negotiation ENABLED to allow negotiation
    of master / slave PHY relationship for clocking at the physical
    layer.  Without negotiation the line clock will not establish
    correctly and physical layers problems can result."

Further:

  http://en.wikipedia.org/wiki/Autonegotiation

    "The debatable portions of the autonegotiation specifications were
    eliminated by the 1998 version of IEEE 802.3. In 1999, the negotiation
    protocol was significantly extended by IEEE 802.3ab, which specified the
    protocol for gigabit Ethernet, making autonegotiation mandatory for
    1000BASE-T gigabit Ethernet over copper."

Note the 'mandatory'...

-- 
Brian Reichert                          <reichert () numachi com>
55 Crystal Ave. #286                    Daytime number: (603) 434-6842
Derry NH 03038-1725 USA                 BSD admin/developer at large    


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