Hi ,
Sorry to interrupt this learning session but I must say add this one thing
that I have learnt in the W. W. of Security:
Try not to use VLANs as a mechanism for enforcing security policy. They are
great for segmenting networks, reducing broadcasts and collisions and so
forth, but not as a security tool.
There are ways to decrease the security risks, something about trunking
ports etc...
More info at:
http://grouper.ieee.org/groups/802/1/vlan.html
Hope this helps!
Jean.
> -----Original Message-----
> From: [EMAIL PROTECTED]
> [mailto:[EMAIL PROTECTED]]On Behalf Of [EMAIL PROTECTED]
> Sent: Monday, September 27, 1999 7:43 PM
> To: [EMAIL PROTECTED]
> Cc: [EMAIL PROTECTED]
> Subject: Re: ENQUIRY
>
>
> What Is a Virtual LAN?
>
> A VLAN is a switched network that is logically segmented on an
> organizational
> basis, by functions, project teams, or applications rather than
> on a physical or geographical basis. For example, all
> workstations and servers
> used by a particular workgroup team can be connected to the
> same VLAN, regardless of their physical connections to the
> network or the fact
> that they might be intermingled with other teams.
> Reconfiguration of the network can be done through software
> rather than by
> physically unplugging and moving devices or wires.
>
> A VLAN can be thought of as a broadcast domain that exists within
> a defined set
> of switches. A VLAN consists of a number of end systems,
> either hosts or network equipment (such as bridges and routers),
> connected by a
> single bridging domain. The bridging domain is supported on
> various pieces of network equipment; for example, LAN switches
> that operate
> bridging protocols between them with a separate bridge group
> for each VLAN.
>
> VLANs are created to provide the segmentation services
> traditionally provided by
> routers in LAN configurations. VLANs address scalability,
> security, and network management. Routers in VLAN topologies
> provide broadcast
> filtering, security, address summarization, and traffic flow
> management. None of the switches within the defined group will bridge any
> frames, not even broadcast frames, between two VLANs. Several
> key issues need to be considered when designing and building switched LAN
> internetworks.
>
>
>
> See :
> http://www.cisco.com/univercd/cc/td/doc/product/software/ios113ed/
> 113ed_cr/switc
> h_c/xcvlan.htm
>
> for more info.
>
> Hope this helps
>
> Marcus
>
> ______________________________ Reply Separator
> _________________________________
> Subject: ENQUIRY
> Author: 97ec090 ([EMAIL PROTECTED]) at unix,mime
> Date: 27/9/99 22:26
>
>
> I had asked all of you few months back through this list for advice on
> acquiring more knowledge about firewalls and was really glad to
> get such a
> lot of help.I want to trouble all of you again .Could anyone please tell
> me about VLANs - what are they exactly and where can I find out
> more about
> them (books , sites etc ) ?
> Thanks in anticipation of your precious time and sorry for any
> inconvinience caused.
>
> warm regards,
> yatindra mahajan.
>
> ------------------------------------------------------------------
> -----------
> YATINDRA MAHAJAN,
> BE-3rd YEAR, AG-5,HOSTEL NO.-5,
> DEPT. OF ELECTRONICS, GANDHI BHAWAN,
> REGIONAL COLLEGE OF ENGINEERING, SVRCET,
> SURAT, SURAT,
> GUJARAT, GUJARAT-395007,
> INDIA. INDIA.
> ------------------------------------------------------------------
> ------------
>
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