netdev
[Top] [All Lists]

Re: 802.1q Was (Re: Plans for 2.5 / 2.6 ???

To: Andrey Savochkin <saw@xxxxxxxxxxxxx>
Subject: Re: 802.1q Was (Re: Plans for 2.5 / 2.6 ???
From: Gleb Natapov <gleb@xxxxxxxxxxx>
Date: Mon, 05 Jun 2000 07:29:33 +0000
Cc: Mitchell Blank Jr <mitch@xxxxxxxxxx>, Ben Greear <greearb@xxxxxxxxxxxxxxx>, rob@xxxxxxxxxxx, buytenh@xxxxxxx, netdev@xxxxxxxxxxx, gleb@xxxxxxxxxxxxxxxxxxxxx, jamal <hadi@xxxxxxxxxx>
Organization: NBase-Xyplex
References: <3938611E.D074F254@candelatech.com> <Pine.GSO.4.20.0006030945230.15626-100000@shell.cyberus.ca> <20000603091818.B48132@sfgoth.com> <20000605102627.A8473@saw.sw.com.sg>
Sender: owner-netdev@xxxxxxxxxxx
Andrey Savochkin wrote:
> 
> Hello,
> 
> I want to ad my $0.02.
> 
> On Sat, Jun 03, 2000 at 09:18:18AM -0700, Mitchell Blank Jr wrote:
> > > Devices map to physical devices i.e ports in your lingo. How many of those
> > > do you see in your average Linux machine?
> >
> > The problem is that if you only think about the "common" network types
> > (ethernet, PPP, etc) this line gets blurred, since there's a one-to-one
> > corresponance between:
> >   * physical devices
> >   * network devices (i.e. things that you can bind IP addresses to,
> >     netfilter based on, tcpdump of)
> >
> > Any sane implementation of VLANs needs to be a network device in the
> > second sense.
> 
> Network devices in the second sense is only an abstraction.
> Linux kernel do not bind IP addresses for devices.  IP address assignment to
> any device is just an entry in routing table "local".  The kernel keeps
> information about the correspondence about IP address and device only for
> backward compatibility to help ifconfig and other obsolete network management
> software to work.  I'm very thankful to Alexey for removing finally the
> long-standing mistake of correspondence between IP addresses and devices from
> the kernel.
> 
> Netfilters isn't a big problem, too.  A specific VLAN-id matching netfilter
> module is a clean and powerful solution.
> 
> I think that the current VLAN implementation slightly abuses the notion of
> device.  And it doesn't relate to the number of devices and the efficiency of
> search algorithms.  The current VLAN implementation is a pure packet-mangling
> code.  It misses one of the most important properties of network devices -
> flow control.  Any code that doesn't provide flow control isn't a device, but 
> a
> code just manipulating of packet contents.
> 
> The current kernel infrastructure for packet mangling may still need some
> adjustments, but it at least exists.  I'm encouraging to consider VLAN
> implementation as just a netfilter module.
> 
> Best regards
>                                         Andrey V.
>                                         Savochkin

As Mitchell said, will I be able to run OSPF between VLANs? I actually
run zebra ospfd on vlans. Zebra has a strong notion of device. It relies
on device up, device done, change ip and other messages from netlink.
Will I be able to do that if vlan will be implemented not as a device.
It looks like vlan will be useless without device interface, at least
for me.

--
                        Gleb.

<Prev in Thread] Current Thread [Next in Thread>