Transcript VLANs Silly Authors Power Points for Chapter #9

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 …:
1.
2.
3.
4.
Port-based VLANs (layer-1 VLANs)
MAC-based VLANs (layer-2 VLANs)
IP-based VLANs (layer-3 VLANS)
Application-based VLANs (layer-4 or policybased VLANS)
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