Transcript VLAN History

VLANs
Virtual Local Area Networks
BA 479
Who are we?
 Ryan Winklepleck
 Senior, Business, MIS, this ‘boy wonder’ is 21-years-old and
still figuring out post-college life, possibly the circus is hiring?
 Kameel Husain
 Senior, Business, MIS, would like to work with graphic designs
and databases. Likes milk, bones are as strong as
antimantium, cage fighter.
 Rob Jerand
 Senior, Business, MIS, always up for kegstands and dollar
beers, enjoys running from the Cops, giving beer cans to the
bums, and my future consists of either being a janitor at
Microsoft, or live in my parent’s basement and do nothing.
 Andrew Grill Jr. III
 Bats: R, Throws: R, Avg: .405, RBI: 132, HR: 59, Triple Crown
MVP, after a gamma blast accident, you don’t want to see him
when he’s angry. Business, MIS, accounting intern at
weyerhaeuser and plans to work there in the future.
VLAN - Brief Introduction
Five W’s and an H…
VLAN Introduction
 What?

“Networks in which computers are assigned to LAN
segments by software rather than by hardware.”
 Who?

Us
 Why?

Often faster, while providing greater opportunities to
manage the flow of traffic on the LAN and Backbone
Network (BN) in comparison to traditional LAN and
routed BN architectures.
VLAN Introduction
 Where?

Hosting Centers and Ethernet Metropolitan
Area Network (MAN)
 When?

Due to their complexity, usually only used for
large networks.
 And the H…
VLAN History
Thought it was going to be How?
VLAN History
 First Products: Segmentable Switches

Allows creation of two or more virtual
switches from a single switch.
 Assigning individual ports to a specific virtual
switch.
 First products allowed switching of multiple
segments on a single switch, as well as
offering a monetary advantage over switched
Ethernet ports which cost $700 or more at
the time.
VLAN Background
However, VLAN Backwards would be NALV…
VLAN Background
 Local Area Networks (LAN)




Generally defined as a broadcast domain.
“Hubs, bridges, or switches on the same physical
segment or segments connect end node devices”
A router is not needed for end nodes on the same
LAN segment to communicate with each other.
However a router is necessary for these devices to
communicate with devices on other LAN segments.
VLAN Background
 To the left, a LAN
environment connected
by routers
 Drawback:
 Routers add latency
that delays the
transmission of data
 Solution?

Switched Network
VLAN Background
 To the right, a LAN
environment connected by
switches.
 Speed and latency
advantages.
 Drawback:
 All end nodes (or hosts)
are in same broadcast
domain, which adds to the
network a significant
amount of traffic that is
seen by all hosts.
 Solution?

Switched Network w/VLANs
Single-Switch VLAN
Single-Switch VLAN
 The VLAN operates only inside one
switch.
 Computers, dozens or even hundreds, on
the VLAN are connected into this switch
and assigned by software into different
VLAN segments.
 VLAN segments act as though they are
connected to the same physical switch
or hub.
Single-Switch VLAN cont.
 It’s possible to have one computer only in
a VLAN. (Servers)
 Four ways in which computers attached
to a VLAN can be assigned to specific
VLANs inside them …:
Port-based VLANs (layer-1 VLANs)
2. MAC-based VLANs (layer-2 VLANs)
3. IP-based VLANs (layer-3 VLANS)
4. Application-based VLANs (layer-4 or policybased VLANS)
1.
Port-based VLANs
(layer-1 VLANs)
 Uses physical layer port number on the
front of the VLAN switch to assign
computers to VLAN segments.
 All computers are physically cabled into a
specific port on the VLAN switch.
 A software is used to instruct the switch
as to which ports are assigned to which
VLAN.
MAC-based VLANs
(layer-2 VLANs)
 Uses data link layer address or physical
address to form VLANs.
 A software is used to instruct the switch
as to which incoming data link layer
addresses are assigned to which VLAN
segment.
 Easier to manage than Port-based.
Multi-Switch VLAN
Multi Switch Approach
 Layer 3
 Layer 4
 IEEE 802.1Q
Layer 3
 Network layer
 serves as the backbone for network traffic
going across different VLANs.
 provides logical routing interfaces to
VLANs on Layer 2 switches. A traditional
network requires a physical interface from
a router to a switch to perform inter VLAN
routing.
Layer 4
 Transport Layer
 Decides on where to send the packets.
 sends incoming packets to one or more
machines which are hidden behind a
single IP address.
IEEE 802.1Q
 allows multiple bridged networks to
transparently share the same physical
network link without leaking information
VLAN Benefits
What is Yreka Bakery spelled backwards?
Benefits
 Performance

VLANs can reduce sending traffic to unnecessary destinations
 Formation of Virtual Workgroups


Segment sections of business (marketing, accounting, etc) by
VLAN
Drawback – distance in physical location, centralized server
farms
 Simplified Administration

Adding, changing, moving user accounts no new
reconfiguration of hubs/routers necessary
Benefits
 Reduce Costs

VLANs can be used to create broadcast domains which can
eliminate cost of expensive routers
 Security


Keep information restricted to only users who need access
Can control boadcast domains, set up firewalls and more
VLAN Drawbacks
Drawbacks
 Costs


Purchasing additional hardware
May need to hire new employee to manage
 Misc.


New users may encounter new problems they are not familiar
with
If users are located on different floors of a building common
resources (such as a printer) could be in inconvenient locations