networkingtechnology for broadcast engineers · networkingtechnology for broadcast engineers part 2...

3/24/11

Networking Technology for Broadcast Engineers – Part 2 1

Networking Technology for Broadcast Engineers

Part 2March 24, 2011

Wayne M. Pecena, CPBE, 8‐VSB, AMD, DRB, CBNT

Texas A&M University

Networking Technology for Broadcast Engineers

Advertised Presentation Scope:

This presentation will provide a Broadcast Focus in major Networking Topics and knowledge of Fundamentals and Principals to equip the Broadcast Engineer with a betterknowledge of Fundamentals and Principals to equip the Broadcast Engineer with a better understanding of TCP/IP addresses, Subnetting basics and Subnet Calculation tools, Gateways and the ISO Structure.It will also cover Switching & Routing protocols and fundamentals, MAC Addresses and VLAN fundamentals to provide a base knowledge upon which to build. And, an introduction to IPv6 will present this eminent major change to the whole IP addressing scheme.

Goals & Deliverables:

What Can You Expect in 2 Hours?

‐ Awareness of Major Networking Topics (broadcast focused)‐ Basic Understanding of Topic Fundamentals & Principals‐Where to Obtain Further Knowledge

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Agenda – Part 2

Review Key Part 1 TakeawaysSubnetting Review

IPv6 FundamentalsWh IP 6a. Why IPv6

b. Addressing Conceptsc. IPv4 to IPv6 Migration Strategies

Switching & Routing Fundamentalsa. Switching Fundamentalsb. MAC Addressesc. VLANSd. Routing Fundamentals & Routing Metricse. Routing Protocolse. Routing Protocolsf. Which Routing Protocol Do I Use?

QoS Basicsa. Why is Quality of Service Needed?b. QoS Typesc. Implementing QoS

Controlling Network Traffic & Security Concerns 3

OSI Model

A Layer Only Interacts With the Layer Below It

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“All People Seem To Need Data Processing”

A Layer Only Provides Capability for the Layer Above to Interact With It

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Encapsulation

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Ethernet ReviewIEEE 802.3

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TCP Handshake & Windowing

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TCP / UDP

TCP ‐ RFC 793

f d “

UDP ‐ RFC 768

“ l ” l• Referred to as a “Connection –Oriented” Protocol

• Guaranteed Or Reliable Data Delivery

– Acknowledgment of Packet Receipt

– Retransmission Occurs if Packet Not Received or Error Occurs

• High Overhead thus Slow

• A “Simple” Protocol or “Lightweight”

• Low Overhead = Fast

• “Best Effort” – Non‐Guaranteed Data Delivery

• Why Use?

– Required for Real‐Time High Overhead thus Slow

• A TCP Conversation Requires Establishment of a 2‐Way “Session” Between Hosts

qApplications ‐ VoIP or Video Transmission”

– Latency More Detrimental Than Data Loss

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NAT & PAT

NAT PAT

• Translates IP Addresses– Limited IP Address Space

– Security

• Static NAT– 1 to 1 Translation

– Hides Real Host IP Address

• Always Used with NAT

• Allows 65,536 “Inside” Hosts To Be Identified by a Socket Address

• Dynamic NAT (PAT)– 1 to Many Translation

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IP Address ClassesPublic & Private

• Class A – 126 Networks / 16,777,214 Hosts– 1.0.0.0 to 126.0.0.0

– PRIVATE ‐ 10.0.0.0 to 10.255.255.255

• Class B – 16,384 Networks / 65,534 Hosts– 128.0.0.0 to 191.255.0.0

– PRIVATE ‐ 172.16.0.0 to 172.31.255.255

• Class C – 2,097,152 Networks / 254 Hosts– 192.0.0.0 to 192.255.255.0

– PRIVATE ‐ 192.168.0.0 to 192.168.255.255

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Private vs Public IP Addresses

• RFC 1918 Established “Private” Address Space– Class A: 10.0.0.0 to 10.255.255.255Class A: 10.0.0.0 to 10.255.255.255

– Class B: 172.16.0.0 to 172.31.255.255

– Class C: 192.168.0.0 to 192.168.255.255

• Key Points:– Private IP Addresses Are NOT Routable Outside the Local Network

– Widely Used in Home & Industry Networks

– May Be Translated With NAT At An Edge Router

• Map Private Address Space to Public Address Space

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Subnetting

• What is a Subnet?

– Logical Subdivision of a Larger Network– Logical Subdivision of a Larger Network

• Why Do We Subnet?

• Efficient Use of IP Address Space• Efficient Use of IP Address Space

• Enhance Routing Efficiency – Reduce Routing Table Size

• Network Management Policy and Segmentation

• Job Security for Network Engineers!

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Subnetting Basics

• Identifies the Boundary Between Network and Hosts

• “Subnetting” Simply Moves the Boundary!• Subnetting Simply Moves the Boundary!– Moves Boundary to the Right

– IP Address Subnetting Applies to All Classes

– Boundary Position Determined by the Subnet “Netmask”

• Expressed in Several Forms:– Doted Decimal Notation (same as IP address)

– Slash Notation (also known as CIDR notation)

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IP Address 165.95.240.100 with Netmask of 255.255.255.0

OR

165.95.240.100 /24

VLSM & CIDR

VLSM ‐ RFC 1009V i bl L h S b M ki (VLSM)

CIDR ‐ RFC 1517, 1518, 1519, 1520

Cl l I d i R i (CIDR)• Variable Length Subnet Masking (VLSM)

– Host Addressing & Routing Inside a Routing Domain

– Allowed “Classless” Subnetting

• Mask Information is Explicit

– Allows More Efficient Use of Address Space

– Allows You to Subnet a Subnet

• Classless Interdomain Routing (CIDR)

– Class System No Longer Applies

– Routing Between Routing Domains

– Class A & B IP Address Exhaustion Pressured Class C Address Space

– Allows “Routing Tables” To Be Reduced by Grouping Contiguous Class C Addresses into One Network

– Allows “Supernets” To Be CreatedAllows Supernets To Be Created

• Combining a Group of Class C Addresses Into a Single Block

– CIDR Notation (slanted notation):172.16.1.1 /16

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What Must Be KnownAbout a Subnet

IP Address and MaskProvides:Provides:

First Network AddressFirst Network Address Assignable to a HostLast Network Address Assignable to a Host

Broadcast Address

192.0.0.0 /24Provides:

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Network Address 192.0.0.0First Network Address Assignable to a Host 192.0.0.1Last Network Address Assignable to a Host 192.0.0.254Broadcast Address 192.0.0.255

“254 Assignable Addresses”

Subnetting Example

Subnet 1

PublicInternet

Subnet 2

38.9.211.0 /24

38.9.211.0 /26

38.9.211.64 /26

38.9.211.2 38.9.211.3 38.9.211.4Default Gateway: 39.9.211.1

Mask: 255.255.255.192

38.9.211.66 38.9.211.67 38.9.211.68Default Gateway: 39.9.211.65

Mask: 255.255.255.192

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Subnet 3

38.9.211.128 /26

38.9.211.130 38.9.211.131 38.9.211.132Default Gateway: 39.9.211.129

Mask: 255.255.255.192

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Special Use AddressRFC 5735

• 0.0.0.0/8 Network Address

• 10.0.0.0/8 Private IP Address Space (RFC 1918)

• 127.0.0.0/8 Loopback Address



• 224.0.0.0/4 Multicast Address Space

• 255.255.255.255/32 Broadcast Address

And many more special use cases………..

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Ports & Sockets

Ports ‐ RFC 1700

ll l i l i

Sockets

“ k ” bi i f• Allows Datagram Multiplexing Between Applications

• Port Numbers Can Be Between 0 ‐65535

– 0–1023 Are Considered Reserved

– 1024–49151 Can Be Registered

– 49152–65535 Are Considered Dynamic or Private

• A “Socket” Is a Combination of an IP Address & A Port Number

• Used for Client‐Server Application Interaction

• IP Address + Port Number = Socket

Socket: 10.10.10.10:80Dynamic or Private

• TCP and UDP Port Numbers Are Independent

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IPv6 FundamentalsRFC 2460

IPv6 Provides Expanded IP Address Space2128 = 340,282,366,920,938,463,463,374,607,431,768,211,456

( h h f )(three hundred forty UNDECILLION addresses)

• 128 Bit Hexadecimal Notation2001:0DB8:0234:AB00:0123:4567:8901:ABCD

• But, IPv6 is More Than Expanded Address Space:

– Re‐Engineered IPv4• Improved Support for Multicasting, Security, & Mobile Aps

• Host Auto‐Configuration

• Security Incorporated

• Traffic Engineering Provisions

• Multicast Incorporated

– IPv6 Does Not Replace IPv4

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IPv4 and IPv6Comparison Summary

IP version IPv4 IPv6IP version IPv4 IPv6

Deployed 1981 1999

Address Size 32‐bit number 128‐bit number

Address Format

Dotted Decimal Notation: 192.0.2.76

Hexadecimal Notation: 2001:0DB8:0234:AB00:0123:4567:8901:ABCD

Number of 232 = 4,294,967,296 2128 = 340,282,366,920,938,463,463,374,607,431,768,211,456Addresses

, , , , , , , , , , , , , , ,

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IPv4 Depletion Situation Report

• Each RIR Received Final /8 in February 2011

IANA F P l f IP 4 0%• IANA Free Pool of IPv4 = 0%.

• Each RIR Currently has IPv4 Addresses to Allocate, But Not Forever!

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Each /8 (Class C) block contains 16,777,216 addresseshttps://www.arin.net/resources/request/ipv4_depletion.html

IPv6 – Is This Adequate Address Space?

• Current Global Demand: – ~24 Million IP Addresses per Month

• IPv6 Address Space:

– Counting /64 subnets it would take ~ 768 Billion years to deplete

– Counting /48 subnets it would take ~ 11.7 Million years to deplete

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IPv4 and IPv6 Comparison

• Internet Protocol version 4 (IPv4, or just “IP”)

– First developed for the original Internet (ARPANET) in spring 1978

– Deployed globally with growth of the Internet

– Total of 4 billion IP addresses available

– Well entrenched and used by every ISP and hosting company to connect customers to the Internet

– Allocated based on documented need

• Internet Protocol version 6 (IPv6)

– Design started in 1993 when IETF forecasts showed IPv4 depletion between 2010 and 2017

l l bl f

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– Completed, tested, and available for production since 1999

– Total of 340,282,366,920,938,463,463,374,607,431,768,211,456 IP addresses available

– Used and managed similar to IPv4

IPv6 Address Format & Notation

128-Bit Address FormatRepresented as a 32 Hexadecimal DigitsRepresented as a 32 Hexadecimal Digits

Subdivided Into Eight Groups of Four Hexadecimal Digits(further summarization may be possible)

2001:0000:0000:0000:0DB8:8000:200C:417Aor

2001:0:0:0:0DB8:8000:200C:417A or

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or2001::0DB8:8:200C:417A

The Shortest Ipv6 Address:::1

“The Loopback Address”

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IPv6 Address Trivia

What Happened to Version 5 of the Internet Protocol?What Happened to Version 5 of the Internet Protocol?

“IPv5 Simply Does Not Exist!

Version 5 was intentionally skipped to avoid confusion, or at least to rectify it. The problem with version 5 relates to an experimental TCP/IP protocol called the Internet Stream Protocol, Version 2, originally defined in RFC 1190. This protocol was originally seen by some as being a peer of IP at the Internet Layer in the TCP/IP architecture and these packets were assigned IP version 5 to differentiate them from

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architecture and these packets were assigned IP version 5 to differentiate them from “normal” IPv4 packets. This protocol never went anywhere, but to be absolutely sure that there would be no confusion, version 5 was skipped over in favor of version 6.”

The Environment Today

• The Industry is Predominantly IPv4 Based Today

• IPv4 Demand Continues…..

• IPv4 Availability Pool Rapidly Decreasing

• IPv4 NAT Use Increasing

• IPv6 Must Be Adopted for Continued Growth

• IPv6 is NOT Backward Compatible With IPv4

• IPv4 and IPv6 Must BOTH Be Maintained for Many Years to Come – “Dual‐Stack Approach”

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My IPv4 Address: 128.194.247.55

My IPv6 Address: 2002:80c2:f737::80c2:f737

My MAC Address: 80:C2:F7:37

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An Approach

• Call to Action – Enterprise Networks– IPv6 Enable Web, Mail, and Public‐Facing Application Servers

– Open Dialog With Your ISP Regarding IPv6 Connectivity Availability & Options

• Call to Action – Content Providers– You Must Be Reachable By New Internet Customers

– Provide IPv4 and IPv6 Connectivity Today

– If Only IPv4 Content is Provided – You Reachability is Determined by Access Provider Transition Solutions

IPv6 Implementation

• Technology Areas of Focus:

– Obtain IPv6 Address Spacep

– Obtain IPv6 Connectivity

• Native

• Tunneled

– Upgrade / Configure Operating Systems

– Upgrade / Configure Routers, Firewalls, DNS

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IPv6 Connectivity

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World IPv6 DayJune 8, 2011

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http://isoc.org/wp/worldipv6day/

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Takeaways

• IPv6 Awareness– More Than Expanded Address SpaceMore Than Expanded Address Space

• IPv6 Address Format & Notation– 128 Bit Number Hexadecimal Number

– Nomenclature ‐ Eight Groups of Four Hexadecimal Digits

• Develop Plans for IPv4 / IPv6 Especially if a Content Provider– Upstream Provider IPv6 Availability?

• NativeNative

• Tunneled

• IPv4 and IPv6 Will Co‐Exist in The Foreseeable Future

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Switching Fundamentals

• Legacy Ethernet Used Hubs– An “Ethernet DA” of sorts – All Bits Go to All Ports

– High Collision Level Due to Shared Media(40‐50% of Bandwidth Consumed by Collision Recovery)

– High Collision Level Yields High Latency

• Switches Allow Segmentation of Network– Allows Dedicated Bandwidth and Point‐Point Communications

– Increased Throughput Due to Zero or Minimal Collisions

– Allows Full‐Duplex Operation

– Increased Security Capability– Increased Security Capability

• Switches Selectively Forward Individual “Frames” from a Receiving Port to a Destination Port

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MAC Addresses

• Media Access Control “MAC” Address

• Unique Hardware Encoded Address

– Burned In Address

– Physical Address

– “Spoofing”

• Hexadecimal Format: 12:3A:4D:66:3A:1C or FF‐FF‐FF‐FF‐FF‐FF

• Switches “Learn” a Table of MAC Addresses

– MAC Table – Maps Destination MAC Addresses to a Port

• 5 Basic Functions of an Ethernet Switch:

L i MAC Add– Learning MAC Addresses

– Aging – How Long is a MAC Address Maintained?

– Flooding

– Selective Forwarding

– Filtering

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Switching Types“Forwarding Method”

• Store – and – Forward

– Receives the Entire Frame Then Makes Decision

– Drops Any Errored Frame Based Upon CRC

– SLOW! (but insures no frame errors)

• Cut – Through

– Look Only @ Destination Address in Header of the Frame

– FAST! (but no error checking)

• Fragment Free (modified Cut‐Through)

– Known as “Runt Free” Switching

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A Simple MAC Table Example

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VLANSIEEE 802.1Q

• Virtual Local Area Network – VLAN

• Allows Separation of Network Devices Across a Common Physical Mediap y

• Why Separate?– Control Broadcast Domains

– Architecture Flexibility

– Security by Isolating Users

• Static Port Based VLAN(s) Most Common– Manual Assignment

• Dynamic VLANS:– MAC‐Based VLAN(s)

• Assignment Based Upon MAC Address

– Protocol‐Based VLAN(s)• Assignment Based Upon Protocol

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VLAN Trunking

• Allows VLAN(s) to be Shared Across Multiple Devices

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VLAN Example

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Switch Port Type Configuration:

Access Link – Member of One VLAN Only Connects to a HostTrunk Link – Carries Traffic From Multiple VLANS Between Switches

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Routing Fundamentals

• Routing is Simply Moving Data From One Network to Another NetworkNetwork

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All Routers Are Aware of All Networks

Routing Protocols

• Routing is Simply the Moving of Data Across Networks

• OSI Model Layer 3 Process

• Routing Involves Two Processes:

– Determining the Best Path The Hard Part

– Actually Sending of the Data The Easy Part

• Static Routing– Stub Routing (used when only one path exists)

• Dynamic Routing– Path is Automatically Determined

• Interior Gateway Protocols (RIP IGRP EIGRP OSPF)• Interior Gateway Protocols (RIP, IGRP, EIGRP, OSPF)– Distance‐Vector

– Link‐State

• Exterior Gateway Protocols (BGP)– Hides Internal Topology of the Network

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Distance‐Vector Routing Protocols

• “Routing by Rumor” – The Overall Network is Unknown, Only Directly Connected Neighbors Are Known by Each Router

• Routing Decision Based Upon a “Distance” or Metric and “Direction” or Vector to Describe

the “Next‐Hop”the Next‐Hop

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Link‐State Routing Protocols

• Network Topology Information is Flooded Throughout the Network

• Each Router Determines its Own “Best Path”

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Routing Protocols

• Interior Gateway Protocols

– Used Within the Same Autonomous System (AS)

RIP RIPv2 IGRP EIGRP OSPF

• Exterior Gateway Protocols

RIP RIPv2 IGRP EIGRP OSPF

VLSM Support No Yes No Yes Yes

Convergence Slow Slow Medium Fast Fast

Configuration Easy Easy Medium Medium Hard

Scalability Poor Poor Good Good Good

Interoperability Yes Yes No No Yes

• Exterior Gateway Protocols

– Used Between Autonomous Systems

• BGP

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A Routing Example

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What Is A “Layer 3” Switch?

• One Box Solution:

– Layer 2 Bridging

• Traditionally Performed in Hardware

– Layer 3 Routing

• Traditionally Performed in Software

• Layer 3 Switch Performs Layer 3 Routing in Hardware

• Eliminates Use of VLAN(s) – Each Port Can Be Assigned to a Subnet

• Not for All Environments– Typically Found in Workgroup Environment

d h– Limited to Ethernet

– Limited to OSPF and RIP Protocols

45Information Technology for Broadcast

Engineers

Switching vs Routing

Broadcast Domain

Router

CollisionDomain

CollisionDomain

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Broadcast Domain

CollisionDomain

CollisionDomain

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Takeaways

• Switching is a Layer 2 Process

• Why Switch?– Breaks the Collision Domain

• MAC Addresses

• VLAN Basics & Applications

• VLAN Trunking Use

• Routing is a Layer 3 Process

• Why Route?– Breaks the Broadcast Domain

• Recognize Routing Protocols• Recognize Routing Protocols

• Interior Gateway vs Exterior Gateway Routing Protocols

• Layer 3 Switching Provides A One‐Box‐Solution

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Quality of Service – “QoS”

• Why QoS?

– Allows Network Traffic to Be Prioritized Based Upon Applicationp pp• Streaming Media

• IP Telephony

• Real‐Time Control (automation)

• Mission Critical Applications

– Network Factors Impacting Quality:

• Throughput

• Dropped Packets

• Errors

• Latency

• Jitter

• Packet Delivery Out‐of‐Order

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QoS continued…..

• Implementing QoS

– VLAN Implementationp

– Bandwidth Over Provisioning

– Traffic Shaping

– DiffServ Implementation• Mark Packets According to Type of Service

• Assigned to Multiple Queues

– Queue Scheduling Algorithms:

• Techniques Raise or Lower Queue Priority

– WFQ ‐Weighted Fair Queuing

– Class Based Weighted Fair Queuing

– WRR – Weighted Round Robin

– HFSC – Hierarchical Fair Service Curve

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QoS continued…..

• QoS Implementation Architecture

– Packet Identification & Marking

– Network Element Provisioning

– End‐End Policy Management

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Controlling Network Traffic

• Traffic Shaping (packet shaping) is Generally Achieved by Delaying Packets

• Used to Optimize or Guarantee Performancep

• Control Volume of Traffic Placed on A Network Segment (ingress)

• Traffic Classification:

– Sensitive

– Best‐Effort

– Undesired Traffic

– File Sharing (P2P Traffic)

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Network Security Concerns

• Focused on Protecting the Network Infrastructure

• Common Threats:

– Packet Sniffers / Port Scanning

– IP Spoofing

– Denial of Service Attacks

– Application Layer Attacks

• Implementation Considerations:

– Know Your Enemy

– Cost

– Human FactorsHuman Factors

– Understand Your Network

– Limit Scope of Access

– Don’t Overlook Physical Security

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Network Security Tools

• Firewall

– Used to Create a “Trusted” Network Segment by Permitting or Denying Network Packets

f ll– Types of Firewalls:

• Packet Filtering

– Stateless

– Statefull

• Application Layer

• Proxies

• NAT

• Detection Tools

– Intrusion Detection Systems (IDS)

• Signature Based

• Anomaly Based

– Intrusion Prevention Systems (IPS)

• Combine Firewall & IDS Functions

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Takeaways

• QoS Basics

• Network Quality Factorsy

• QoS Implementation Techniques

• Traffic Shaping Basics

• Awareness of Network Security Threats

• Awareness of Network Security Implementation Considerations

• Firewall Types

• IDS/ IPS Use

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Visualizing The “Internet”

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Current “IPv4” Internet Routing Table:

353,698 BGP Routes(Monday 3-21-11)

Routing Trivia

• First “Router” as We Know is Was the “Interface Message Processor – IMP”

• Developed in the Late‐60’s for ARPANET

• First Message “lo” Was Sent on October 29, 1969 fromUCLA to the Stanford Research Institute

• After Recovery From a System Crash, the Word “login” Was Successfully Transmitted

• Life Has Never Been the Same Since!

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Reference Sources:• My Favorite Reference Texts:

– Ethernet: The Definitive Guide – Charles Spurgeon

– Cisco CCNA Simplified – 3rd Edition – Paul Browning

– Cisco IOS in a Nutshell – 2nd edition – James Boney

– Network Maintenance & Troubleshooting – 2nd Edition – Neal AllenNetwork Maintenance & Troubleshooting 2 Edition Neal Allen

– Network Warrior – Gary Donahue

– The Illustrated Network – Walter Goralski

– Wireshark Network Analysis – Laura Chappell

• Subnet Calculation Tools:

– www.subnet‐calculator.com

– www.bitcricket.com/ip‐subnet‐calculator.html (Ipv4 and IPv6 capable)

– www.solarwinds.com/products/freetools/free_subnet_calculator.aspx

– IpHONE Aps (iTunes Store):

• IP CalcIP Calc

• IP Calculator

• RFC Documents:

– www.rfc‐editor.org

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Reference Sources:

• RFC Documents:– www.rfc‐editor.org

• IPv6 References:i– www.arin.net

– www.getipv6.info

– www.GoGo6.com

– http://test‐ipv6.com/

– http://testmyipv6.com/

– http://www.ipv6forum.com/

• Internet Routing Metrics:– http://bgp.potaroo.net/

– http://www.internettrafficreport.com/

• World IPv6 Day– http://isoc.org/wp/worldipv6day/

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Wrap – Up? Questions ?

Thank You for Attending!

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Thank You for Attending!

Wayne M. Pecena, CPBE, 8-VSB, AMD, DRB, CBNT

Texas A&M [email protected]