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  • 1.  UDP Fragmentation Ethernet interface

    Posted 10-17-2022 05:44
    Hi,

    Cant find anything in the KB about this, however, i am wondering if UDP packets are fragmented by default on the SRX300 Ge interfaces?

    Reason i ask is reviewing documentation for some VoIP handsets outlined that UDP packets must NOT be fragmented for BLF to work across the business and currently, BLF is not working.

    Thanks,
    Ryan

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    Ryan Todd
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  • 2.  RE: UDP Fragmentation Ethernet interface

    Posted 10-17-2022 08:47
    Packets would only be fragmented if the data size exceeds the data mtu available.

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    Steve Puluka BSEET - Juniper Ambassador
    IP Architect - DQE Communications Pittsburgh, PA (Metro Ethernet & ISP - Retired)
    http://puluka.com/home
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  • 3.  RE: UDP Fragmentation Ethernet interface

    Posted 10-17-2022 09:12
    Is UDP fragmentation allowed by default? or is the packet dropped?

    Thanks Spuluka!

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    Ryan Todd
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  • 4.  RE: UDP Fragmentation Ethernet interface

    Posted 10-18-2022 06:08
    Yes, default behavior is to fragment ip packets as needed per the size.

    The ip RFC behavior would be for the application to set the do not fragment bit to inform routers to drop and not fragment.

    ------------------------------
    Steve Puluka BSEET - Juniper Ambassador
    IP Architect - DQE Communications Pittsburgh, PA (Metro Ethernet & ISP - Retired)
    http://puluka.com/home
    ------------------------------