11 bootp message fields server ip address returned in

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Unformatted text preview: tP - Message Fields Server IP-address Returned in boot reply by server Router IP-address Server is part of another Subnet IP-address of the BootP relay Client Hardware-address MAC-address of client (C) Herbert Haas 2005/03/11 12 The "Server-IP-address" contains the IP address of an optional boot server. If a gateway does decide to forward the request, it should look at the 'giaddr' (gateway IP address) field. If zero, it should plug its own IP address (on the receiving cable) into this field. It may also use the 'hops' field to optionally control how far the packet is reforwarded. Hops should be incremented on each forwarding. For example, if hops passes '3', the packet should probably be discarded. The Client's HW address is needed to find an entry in the address-table at the BOOTP server. 12 BootP - Message Fields Server Host Name Optional server host name Bootfilename Contains directory path and filename of the bootfile Vendor Specific Area Optionally contain vendor information of the BootP server RFC 1048: also possible to mention the subnet mask, hostname, domain name, DNS, etc (C) Herbert Haas 2005/03/11 13 Optionally, the servers domain name can be specified. This field is limited to 64 bytes. The "Bootfilename" contains the directory path and filename of the bootfile, which is located at the server specified above. 13 Dynamic Host Configuration Protocol (DHCP) A dynamic solution with even more parameters (C) Herbert Haas 2005/03/11 14 14 Principles Nearly identical to BOOTP Slightly extended messages only More parameters Uses UDP communication Client-Side: Port 67 Server-Side: Port 68 Based on a leasing idea! Dynamic configuration RFC 2131 and RFC 2132 (C) Herbert Haas 2005/03/11 15 The Dynamic Host Configuration Protocol works nearly identical to BOOTP. DHCP uses the same message format with only slightly chances. DCHP based on a leasing idea. The IP address will be leased from the server to the client for a special time, after this time expired the client need to send his request again. 15 Flexible Confi...
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This document was uploaded on 02/12/2014.

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