On Wed, Apr 15, 2009 at 8:20 PM, Mike Ayers <mike_ay...@tvworks.com> wrote: >> From: Dave Shield [mailto:d.t.shi...@liverpool.ac.uk] >> The specs implicitly allow an arbitrary length string >> (although there may be some limit imposed by ASN.1 >> or BER - I'm not sure offhand). > > Over a million octets, IIRC. > >> > Is there some defacto standard for maximum length. >> >> The main restriction will be from MIB objects that take >> a community string as their value. > > There's another aspect to take into account. SNMP is run over UDP in > the (vast) > majority of cases, and therefore all information in a request or response > must fit into a > single UDP packet. I'd have to consult references for the exact number, but > there's > about 1300+ bytes available for UDP packets over a standard ethernet link. > Since > you need to put varbinds in the packet, too, the space fills up quickly.
An UDP packet can contain at most 65527 bytes data. UDP packets that do not fit in a single Ethernet packet (max. 1500 bytes when not using GbE jumbo frames) get fragmented over multiple Ethernet packets. See also http://en.wikipedia.org/wiki/User_Datagram_Protocol. Bart. ------------------------------------------------------------------------------ This SF.net email is sponsored by: High Quality Requirements in a Collaborative Environment. Download a free trial of Rational Requirements Composer Now! http://p.sf.net/sfu/www-ibm-com _______________________________________________ Net-snmp-users mailing list Net-snmp-users@lists.sourceforge.net Please see the following page to unsubscribe or change other options: https://lists.sourceforge.net/lists/listinfo/net-snmp-users
