The Foundation presents

Third Thursday: The Evolving Internet

and Your BusinessMay 17, 2007

Thanks to Dunwoody College

www.dunwoody.edu

Timeline

• 1992 - Email/FTP

• 1995 - Websites

• 1997 - Web browsing

• 1998 - Google

• 2002 - Intranet (SharePoint - 04-06)

• 2003 - Disaster Recovery Planning

• Broadband and High Bandwidth

• 2004 - VoIP

2007 Maturing of Techs

• Virtualization

• Offsite

• DR

• Remote Backup

• ASP Models

• Online ERP apps

• Sharepont

• Large Pipes

Data

Data

Data

Segments

Packets

Frames

Bits

The OSI Model

Application (telnet, http)

Presentation (e-mail, mime)

Session (named sockets)

Transport (TCP, UDP)

Network (IP, IPSec, ARP)

Data Link (Ethernet, Fibre, 802.11g/n)

Physical (hubs, 10-BaseT)

Packets

Frames

Bits

Where it’s at - Layers 1-3Network (IP, IPSec, ARP)

Data Link (Ethernet, Fibre, 802.11g/n)

Physical (hubs, 10-BaseT)

• Ethernet - Layers 1,2 - both interface and transport

• Switches are at Layer 2

• Routers are at Layer 3

Switches

Frames Data Link (Ethernet, Fibre, 802.11g/n)

What is a switch, really?

• Larry’s definition: Creates one or many independent networks, enables concurrent communication at different speeds

• Focuses on the MAC address level

• Decides path for frames

• Allows full-duplexing - talking at the same time

Isn’t that just like a hub?

• A hub is a Layer 1 device

• Permits physical connection, but offers no traffic discretion

• Traffic can be seen and/or collide from all ports in any direction

• The ultimate in unmanaged networking

• Unmanaged - No configuration interface or options

• Managed - Wide variety of configuration options

• Smart - Limited version of managed switch

• Gigabit - Highest wire-based speed for commercial applications. Highest collision probability too!

Types of switches

What can I do with a (good)switch?

• Use Ethernet, Fibre Channel, wireless

• Seamlessly traverse all of these mediums

• Set port priority

• Filter traffic per device

• Create VLAN’s (Virtual Local Access Networks)

• Use spanning trees to detect your network construction

• Monitor links using SNMP

• Bonding/Trunking

Switches handle Frames

MAC Header(14 bytes)

Destination MAC Address

80 00 20 7A 3F 3E

Source MAC Address

80 00 20 20 3A AE

EtherType

80 00

Data(46-1500 bytes)

PayloadIP, ARP, etc.

Ethernet Type III Frame(64-1518 bytes)

CRC Checksum (4 Bytes)00 20 20 3A

Component parts of a Frame

Setting port priority

• Used in tandem with other policies to ensure quality of service

• There is a business need for certain groups to have a data priority

• Certain physical ports assigned to purposes greater than others

• Best use: Bandwidth needed at all costs (VoIP, graphics team)

Making a VLAN

• Used in tandem with other policies to ensure quality of service

• Carves up the network into traffic groups

• Common uses: storage areas, VoIP

• Ports are tagged with a VLAN identifier across switches

A simple VLAN

Trunking

• Used in tandem with other policies to ensure quality of service

• At the simplest level, allows you to bundle VLANs and ports together - benefits of aggregation

• Focus on distribution of resources for optimal network function

A simple trunk

Why are good switches important?

• In combination with power and cabling, the basis of your communication

• 80% of network failures occur in Layers 1-3

• Detection not possible on low-end switches

• Assuring quality connections becomes possible

• Can replace many other devices in a single management center

• Port negotiation issues between vendors - code updates across the board - standardization helps network support as well.

Routers

Packets Network (IP, IPSec, ARP)

Routers are intersections

What is a router, really?

• Larry’s definition: A junction between one or more networks

• Focuses on the IP address level

• Decides path for packets

• Edge or core: Home users are familiar with edge routers that connect to the Internet, core routers work within a network

What can I do with a router?

• NAT (Network address translation)

• Route IP traffic between different networks

• Move traffic between VLAN’s

• VPN (Virtual Private Network)

NAT explained

• Converts real world addresses to local addresses

• Acts as a natural firewall to prevent incoming requests

• Tracks destinations and ports - different NAT types allow/restrict more heavily

• Problem services that must be addressed: FTP, IPSec (VPN), VoIP

Route IP Between Networks

• Enables you to get from point A to point B. Even though it’s often more like point A to point Z.

• A well-honed configuration table keeps paths well defined.

• In smaller networks, an important traffic cop for intelligent handling of communication

1 Destination - 11 hops

1 10.55.93.1 (10.55.93.1) 2.142 ms 2.445 ms 4.400 ms 2 71.5.110.1 (71.5.110.1) 117.125 ms 122.690 ms 120.718 ms 3 71.5.107.161 (71.5.107.161) 123.949 ms 134.323 ms 130.106 ms 4 67.109.64.93.ptr.us.xo.net (67.109.64.93) 127.231 ms 139.356 ms 144.822 ms 5 p6-3-0-0.mar2.chicago-il.us.xo.net (207.88.84.61) 159.507 ms 149.822 ms 6 p4-2-0-0.rar2.chicago-il.us.xo.net (65.106.6.205) 168.493 ms 164.606 ms 7 p1-0.ir1.chicago2-il.us.xo.net (65.106.6.138) 169.688 ms 182.233 ms 8 206.111.2.14.ptr.us.xo.net (206.111.2.14) 244.645 ms 342.918 ms 9 yahoo-4.ar2.dca3.gblx.net (64.208.110.122) 227.710 ms 214.968 ms10 ge-1-0-0-p110.msr2.dcn.yahoo.com (216.115.108.45) 231.577 ms ge-1-0-0-p100.msr1.dcn.yahoo.com (216.115.108.41) 111.548 ms 140.541 ms11 ge3-1.bas1-m.dcn.yahoo.com (216.109.120.149) 151.243 ms ge10-2.bas2-m.dcn.yahoo.com (216.109.120.249) 186.563 ms ge7-2.bas1-m.dcn.yahoo.com (216.109.120.201) 197.609 ms

Example of IP routing

Intra-VLAN Routing

VPN

• Router acts a traffic cop as always

• Defines and limits access to certain areas on local network from outside

• Builds a bridge from outside/inside or from network to network

• If you’re on a pleasure trip, take a ferry. If you’re on mission, you need a submarine.

• Replaces/augements leased lines (i.e., dedicated T1)

Big World VPN

Why do I need a decent router?

• What’s better than having a traffic light? An intelligent cop at every corner

• 80% of network failures occur in Layers 1-3

• Today’s routers are like mini-computers, running programs, encrypting traffic, etc.

• Working with decent switches, networks can gain complexity and maintain their zip

• Business needs: secure private connections, FTP, mail servers, wireless

The Big Picture

• The basis of your business begins at power

• How you connect to that power (your wires)

• What interfaces your wires use to get to your desktop (routers and switches)

• Using this model start at layer one and work up

• Big companies and small alike build mansions on dirt roads

• Pick a single vendor and save yourself trouble

THE FOUNDATION311 7th Avenue North Mpls, MN

612-465-0700www.fndtn.com