On Thu, 2003-10-09 at 07:04, Heilai Renett wrote: > >What is the size of IP datagram on linux operating system. > > It depends on the MTU of the physical interface. For Ethernet, it usually is > 1500. > > Heilai > > _________________________________________________________________ > MSN 8 helps eliminate e-mail viruses. Get 2 months FREE*. > http://join.msn.com/?page=features/virus > > - > : send the line "unsubscribe linux-net" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html There are many kinds of Ethernet: there's Ethernet (outdated), Ethernet II (what we use), Ethernet II + VLAN (802.3q), 802.3 SNAP (http://www.firewall.cx/ethernet-frames-802.3-snap.php); and all have different logical/physicals formats. When anyone refers to Ethernet, its the Ethernet II standard unless explicitly stated otherwise. There are two IP standards, IPv4 (RFC 791) and IPv6. When anyone refers to IP, they are talking of IPv4. IP packet size can range from 20 bytes (hdr + 0 data) to 65535 bytes. This is a layer 3 PDU. The IP packet is then encapsulated in a layer 2 technology e.g. Ethernet. Ethernet has an MTU (Maximum Transmission Unit i.e. max data size) of 1500 bytes. If the IP packet size exceeds the MTU then the IP packet is fragmented into parts and these parts are reassembled at the destination to yield the original IP packet. The theoretical range of IP packets is specified by the RFC (Linux is RFC-compliant), and the actual transmitted size of any legal packet depends on what you have filled in it and whether it was fragmented to fit into the MTU of the underlying layer 2 technology. Thus the size of the IP Packet does not depend on the Linux operating system. HTH -- Ranjeet Shetye Senior Software Engineer Zultys Technologies Ranjeet dot Shetye2 at Zultys dot com http://www.zultys.com/ The views, opinions, and judgements expressed in this message are solely those of the author. The message contents have not been reviewed or approved by Zultys. - : send the line "unsubscribe linux-net" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
