Path: ...!news.misty.com!weretis.net!feeder6.news.weretis.net!tncsrv06.tnetconsulting.net!tncsrv09.home.tnetconsulting.net!.POSTED.omega.home.tnetconsulting.net!not-for-mail
From: Grant Taylor <gtaylor@tnetconsulting.net>
Newsgroups: comp.os.linux.misc
Subject: Re: I never thought of this scenario
Date: Sun, 21 Apr 2024 14:58:22 -0500
Organization: TNet Consulting
Message-ID: <v03r4u$32u$2@tncsrv09.home.tnetconsulting.net>
References: <uv2g3g$39k$1@tncsrv09.home.tnetconsulting.net>
 <uvhtft$3th0n$6@dont-email.me>
 <uvhv0m$kq3$1@tncsrv09.home.tnetconsulting.net>
 <uvs61u$2g9b9$5@dont-email.me> <uvsv4f$3cvv$1@news1.tnib.de>
 <uvv1qf$392q8$2@dont-email.me> <uvve26$3f4ea$1@dont-email.me>
 <wwvh6fwxy7q.fsf@LkoBDZeT.terraraq.uk> <v0108c$3q01h$1@dont-email.me>
 <v0111s$3q1fd$1@dont-email.me> <v013pv$3qmkf$1@dont-email.me>
 <v014gp$3qp0c$1@dont-email.me>
 <v017q3$td0$4@tncsrv09.home.tnetconsulting.net>
 <v018mo$3rj12$1@dont-email.me> <v02p3o$894n$2@dont-email.me>
Mime-Version: 1.0
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 7bit
Injection-Date: Sun, 21 Apr 2024 19:58:22 -0000 (UTC)
Injection-Info: tncsrv09.home.tnetconsulting.net; posting-host="omega.home.tnetconsulting.net:198.18.1.140";
	logging-data="3166"; mail-complaints-to="newsmaster@tnetconsulting.net"
User-Agent: Mozilla Thunderbird
Content-Language: en-US
In-Reply-To: <v02p3o$894n$2@dont-email.me>
Bytes: 3190
Lines: 45

On 4/21/24 05:17, The Natural Philosopher wrote:
> Not at all true in the case of address translation, routing protocols, 
> traffic shaping and the like.

Network address translation isn't routing.  NAT happens /after/ routing 
happens.

Routing protocols aren't routing.  They exchange route information to 
program routing tables.  Routing uses said information to do the 
routing.  Routing protocols aren't required for routing.  Manually 
entered static routes work perfectly fine.

Traffic shaping isn't routing.  It's altering how fast traffic is sent out.

Routing is deciding which interface to send the packet out and doing so. 
  Other things may be done before and / or after routing.  But routing 
is it's own independent thing.

> DHCP is similar in that the on;y thing a router has to do is determine 
> its a UDP broadcast, and if it is, work out where to send it, and what 
> return address to give it if any..

Nope.

> One would expect the router to simply spoof a MAC address on its 
> interface, and relay responses to that MAC address back to the client 
> network.

Nope.

> In short its acting like an ethernet switch or bridge

That's proxy ARP, which is a form of routing in it's own way.

> I am more curious as to how the DHCP server 'knows' which network 
> address to give the client, but not interested enough to look it up. :-)

See my most recent reply for a description of how DHCP relay agents 
interact with DHCP clients and DHCP servers.  Hint:  It populates a 
field in the DHCP packet, changes the source to be it's own unicast IP, 
and changes the destination to be the remote DHCP server's unicast IP.



-- 
Grant. . . .