8/3/2018. IP for Technicians. Agenda. Instructor Introduction

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1 IP for Technicians EST CEDIA Expo San Diego Agenda Introduction What Is IP? The IP Address Subnets and Gateways Network Address Translation Domain Name System MAC Address Troubleshooting Tools Threats on the Internet Network Security Conclusion Instructor Introduction Instructor Name Job description Credentials Certifications Contact information 1

2 Learning Objectives Discuss the importance of the growth in IP networking Explain common networking protocols such as TCP, UDP, IP, DHCP, DNS, and NAT Select install and configure consumer routers for wired environments Create and implement IP addressing schemes for connected network devices (computers, AV, lighting, control, etc.) Create system documentation for IP networks What Is IP? What Is IP? TCP/IP (Transmission Control Protocol/Internet Protocol) is the basic communication language or protocol of the Internet and is DIGITAL TCP/IP refers to two separate protocols: TCP and IP 2

3 So What? IP is become one of the most important skills sets in the residential custom integration industry This is happening because: Scalable Flexible Simple Easy to interface IPLeverages technology Scalability Not Point to Point Almost unlimited number of devices No limit on size of network PAN LAN WAN Flexibility Structured cabling systems allow flexibility on cable usage Physical medium is largely irrelevant o Copper o Wireless o Fiber Category rated cable is ubiquitous o Cat5: Virtually obsolete o Cat5e o Cat6 o Cat6a o Cat7 3

4 Simplicity One network, multiple services o Audio distribution o Video distribution o Telephony o Video conferencing o Control o Security/CCTV o Data One set of skills to learn and master One network to maintain Interfacing Web pages ubiquitous Seamless meta-data display Huge range of UIs o Phones o PDAs o Dedicated remotes o The TV Easy to access the LAN from the WAN OSI Reference Model Open Systems Interconnection Developed by the International Organization for Standardization (ISO) Guidelines to be used by manufacturers developing communication systems o Not a strict standard Allows for device interoperability 4

5 OSI Model Layers 7 Layer Model Breaks down complex communication process into distinct functions Each layer serves the layer directly above it and is served by the layer directly below Key advantage for technicians: o TROUBLESHOOTING OSI Model Layer Examples OSI layer Application Presentation Session Transport Network Data link o LLC o MAC Physical Network Component Web (http) GIF SQL TCP IP Ethernet Ethernet Sunset.gif = HOST Data 7. Application 6. Presentation HOST 7. Application 6. Presentation 5. Session 4. Transport Segment 3. Network Packet 2. Data LinkFrame 5. Session Encapsulation Decapsulation Data 4. Transport 3. Segment Network 2. Packet Data Link Physical 1. Frame Physical Routing 5

6 Receive 8/3/2018 OSI Model Components OSI Layer Protocol Data Unit (PDU) Example Network Component Application Data stream Web (http) Presentation Data stream GIF Session Data stream SQL Transport Segment TCP Network Packet IP Data link Frame Ethernet o LLC o MAC Physical Bit Cabling OSI Model Devices OSI Layer Common Network Devices Application Network host or client Presentation (Laptop, desktop, Blu-ray, etc ) Session Transport Network Router Data link Switch, bridge, WAP o LLC o MAC o Network interface card (NIC) Physical Hub, cables OSI Pneumonic OSI Layer Top to Bottom Bottom to Top Application All Away Presentation People Pizzas Session Seem Sausage Transmit Transport To Throw Network Need Not Data link Data Do o LLC o MAC Physical Processing Please 6

7 OSI vs. TCP/IP OSI Layer TCP/IP Model Application Presentation Application Session Transport Transport Network Internet Data link o LLC Network access o MAC o AKA Network interface Physical Hub, cables The Physical Layer IP in the home usually runs over Ethernet, which is defined as: o IEEE o Collection of IEEE standards o Generally a LAN technology with some WAN applications When using copper cable, this is almost universally twisted pair (CAT5e, CAT6, CAT6A) IP can also run over fiber and wireless technologies Physical layer failures are the biggest failure mode on IP networks An untested cable does not work! Not Ethernet Remember, just because it can be sent down twisted pair, does NOT mean it is Ethernet These devices use twisted pair to carry signals other than Ethernet The networks that Ethernet and these devices use may appear on the same patch panel, BUT these devices DO NOT CONNECT TO THE ETHERNET NETWORK 7

8 Binary Refresher A bit is a binary digit, taking a value of either 0 or 1 A byte is a unit of measurement of information storage, most often consisting of eight bits Bits use a small b; Bytes use a capital B Transmissions speeds are measured in bits per second; storage is measured in Bytes Binary Example TCP and UDP There are two types of Internet Protocol (IP) traffic o TCP (Transmission Control Protocol) o UDP (User Datagram Protocol) TCP Reliable Connection-oriented Segment retransmission and flow control through windowing Segment sequencing Acknowledge segments UDP Unreliable Connectionless No windowing or retransmission No sequencing No acknowledgement 8

9 Packets, and the Post You write a book You split it into chapters and put each into a numbered in order, addressed envelope to send to your publisher You post all the envelopes into the post box Packets, and the Post (cont.) They travel through the postal system (together?) They are delivered (together?) The publisher opens the envelopes in order What if there is one missing? It might arrive late, or have been lost TCP/IP has many similarities What about UDP? LANs and WANs A LAN is a Local Area Network and is the network within your home or office A WAN is a wide-area network and is the network outside your home or office; most commonly the Internet A device that connects 2 networks together is defined as a router 9

10 LANs and WANs Analogy Unique on the planet; there is only one of them and it has a public postal address: 100 King St London W6 0SZ, UK LANs and WANs Analogy (cont.) Go Through Its Locked Front Door and You find some post boxes marked: o Apartment 1 o Apartment 2 o Apartment 3 etc. How many post boxes are there in the world marked Apartment 3? Hundreds of thousands? A Basic Home Network 10

11 The IP Address The IP Address Rule #1 EVERY device on a network must have a unique IP address An IP address consists of 4 octets IP Address Restrictions Restrictions on IP addresses: o You cannot just make up a number o Handed out by RIPE; similar to a phone company giving out phone numbers o This is really important because IP addresses used on a LAN cannot be used on the Internet and vice-versa Each number must be between 0 and 254 o Computers work in binary, and 255 is the largest number you can fit in 8 bits o 255 is reserved as a Broadcast address and should not be used in device addresses o Some parts of the IP address space are reserved 11

12 Reserved IP Addresses Private IP addresses o Three possible ranges to choose from: Class A private Address range: 10.x.x.x, Class B private Address range: x.x x.x Class C private Address range: x.x Class C addresses are by far the most commonly used on home networks Needed because there are not enough IP addresses for every device on the planet to have a unique IP address Assigning IP Addresses: DHCP Automatically Using DHCP (Dynamic Host Configuration Protocol) For devices that get switched on and off a lot or removed and used on other networks PCs, PDAs and laptops The device may get a different IP address every time it is switched on; does it care? Assigning IP Addresses: Static Manually (Static) You configure a device with an IP address o This never changes o You (and other devices) always know what it is Used for devices that are left switched on: Servers, Wireless access Points, Media players, Control processors etc. 12

13 Assigning IP Addresses (cont.) A suggestion for a x network o Put the router on o Setup the router to have a DHCP pool from to o Use for static IP addresses Document everything! Why Do We Need A Router? WAN addresses are not on the same Subnet as LAN addresses A network device will know this (using its Subnet Mask) and will look for a route to send the information down In most cases, this will be the default gateway on Windows The default gateway will be the router that you have installed What Does The Router Do? A router is connected to two networks (in most cases, the LAN and the Internet) When a router receives a packet of information, it first looks to see where the packet is for o If it has received it on the LAN side, it checks to see if the packet is to go to a WAN address, and vice-versa If the packet is to be sent from the LAN to the WAN, the router passes on the packet to the Internet 13

14 Router Features Firewall Not the same as virus protection Prevents unauthorized access to the LAN from the WAN Careful setup! Can block all access to the Internet DHCP server Advanced Features Most modern routers should have a configurable DHCP server Make sure that you set the pool to be the same IP range! VOIP server: Voice Over Internet Protocol VPN Server: Virtual Private Network QoS: Quality of Service A Basic Home Network Exercise In pairs, take 10 minutes to prepare an IP address list for a project 14

15 Subnets and Gateways Subnets and Gateways Unless you are Cisco certified, run very fast if you come across a Subnet mask that IS NOT A Subnet mask is NOT an IP address The Subnet Mask A Subnet mask is used by a device to ascertain if a another device it wished to communicate with is on the same network or a different network Let s see how this is done Is a device With this Subnet mask that wishes to communicate with the following:

16 Network Address Translation Network Address Translation The x.x network range is not a valid WAN address No WAN network device will be able to send you information or replies The router changes the packet to claim that it came from its WAN address rather than the LAN address that it actually came from It remembers the packet that was sent and forwards the reply to the appropriate LAN address A Basic Home Network 16

17 Domain Name System Domain Name System The DNS is like a big directory that converts words (that analog humans understand) into IP addresses (that the digital Internet understands) = The DNS server is usually the router Discussion What are the effects of leaving out a DNS server? 17

18 MAC Address The MAC Address The MAC Address A media access control address (MAC address) is a unique identifier assigned to every network interface when it is manufactured It is a 48 bit number made up of six groups of two hexadecimal figures i.e. 10:93:e9:0f:89:78 This gives around 284 trillion possible addresses Every network interface ever made has a unique MAC address Why Do We Need MAC Addresses? It fits into to the Open Systems Interconnect (OSI) model IP addresses change; MAC addresses are permanent (if you move a device, it s MAC moves with it) DHCP; uses MAC addresses to assign an IP address to a device An Ethernet switch is usually a Layer 2 device and will use MAC addresses to switch data to the correct port 18

19 Your Computer On a PC It is important to be able to find out what the networking settings are on your computer This is best done by bringing up a command prompt and typing in: o ipconfig/all o The /all is optional and gives details of all network adaptors even if they are not connected Your Computer (cont.) On a Mac Go to System Preferences, then click on Network, then click on Advanced These tools will give you your computer s IP Address, its Subnet mask, its gateway address (called Router on a mac), its DNS servers and its MAC address What Can Go Wrong? Lots of things can go wrong; just one incorrect setting can go unnoticed for months, and be very difficult to track down Incorrect gateway; no access to/from outside Incorrect Subnet mask; much harder to track down Get it right first time or spend months tracking down a single incorrect digit! 19

20 Troubleshooting Tools The Real World Panic in Private! Do as much set-up off site as possible Find a range of networking gear and stick with it Make sure YOUR laptop is well maintained and reliable Before you do anything else, make sure that the Physical Layer has been tested; all cables should be qualified (recommended as per TIA- 570-B ) or certified (as opposed to just verified) Troubleshooting Tools PING IPCONFIG TRACEROUTE Type ping into Command Prompt If you get a response, the device you are pinging will have basic network connectivity Type ipconfig into Command Prompt Shows the IP configuration of that computer Type tracert into Command Prompt Shows the path taken to reach a host 20

21 IPv6 Most things we have taught you today will have a limited lifespan IPv4 (current 32 bit addressing) limits us to 4,294,967,296 unique addresses IPv6 (128 bit addressing) will give addresses, or (50 octillion) for each of the roughly 6.5 billion people alive today! Threats on the Internet Threats on the Internet Viruses Worms Spyware Spam Phishing Identity theft 21

22 Viruses Virus is a catch-all phrase for many computer security threats Viruses are programs that spread from one computer to the next o Normally this requires some form of user action o E.g. virus Anna Kournikova naked pics will probably contain a virus that runs when you open the attachment Viruses are becoming less common as more sophisticated attacks that require no user action develop Worms Worms are designed to automatically spread from computer to computer using exploits in software o Security holes (common in large programs like Windows) that are able to be attacked automatically Once a worm has infected a computer, it will in turn attempt to infect other computer Often used to create botnets, or groups of computers that can be controlled by another party for malicious or financial gain Spyware Software installed that performs tasks behind your back Often packaged with legitimately useful software Spyware can: o Listen to your key presses o Track your Internet browsing habits o Send information about you to marketing companies o Pop up extra windows when you browse the web Normally not malignant, just annoying and wasteful 22

23 Spam Spam is the electronic equivalent of junk mail Spam in itself is not normally malicious, just annoying o Costs money to receive (bandwidth costs) o Makes checking for solicited harder o Can have malicious payload attached Botnets can act as spamming systems Phishing Social engineering and identity theft Relatively new phenomenon with the rise of Internet banking s sent out in spam to look like official s Ask you to input your details to a website that looks exactly like target website Record details and then use them on the real website to take your money! Like fake ATM machine/card reader in the real world Identity Theft Online identity theft becoming real problem Usernames and passwords compromised through other techniques Normally not due to direct hacking of your computer, but of the computers of companies that you use addresses are often usernames and people often reuse passwords o Get access to one system, get access to many! 23

24 Network Security Network Security To secure a network Set up Hardware Software Wetware properly No network can be completely secure Hardware Turn on all firewalls and configure correctly Use VPNs if possible o Use port translation when not and re-locate the default ports to alternate ports Make sure the router is not configurable from the Internet Change default passwords Change default SSID on wireless access points (WAP) Know where your cabling is connected o Can someone else access your network? o Consider segregating wired and wireless networks 24

25 Hardware (cont.) Choose appropriate hardware for the job o No need to spec budget routers for any job Ensure firmware is up to date regularly Logging access attempts on firewalls can highlight a problem area in your security Software Basics: Install antivirus software Turn on software firewall in operating systems (Windows, Mac, Linux) Set up limited user accounts and only use administrator level accounts when installing software Important: Make sure software is set to automatically update Thinking you are secure when you are not is worse than no security at all Automatic updates avoid user intervention Pros far outweigh the cons Software (cont.) Avoid running services unless absolutely required o Outsource FTP, website; cheap and easy Turn on logging in software if possible; it can show when and how problems occur 25

26 Wetware AKA The client and their family Biggest security risk is the user Make sure that there is no user intervention required to keep things secure o Automatic updates should be automatic Train client not to ignore warnings that software is out of date Wetware (cont.) Warn of the dangers of making system insecure Create a security policy for the whole family by: o Establishing safe browsing habits o Raising concern about where to browse o Decreasing client reliance on antivirus Make sure they understand the policy The Security Policy Common sense Never Tell Anyone Without Good Reason: Usernames Passwords 26

27 If Problems Occur Common symptoms of a security problem: o Random files appearing o Major slowdown of computer o Slowdown of internet access o Error messages (e.g. bouncing , websites not loading) Disconnect from the Internet Turn off computer Call in an IT specialist New Skills Network infrastructure design and installation IP is the dominant protocol IP WILL become the dominant protocol in our industry so do not ignore developing this skills set Conclusion Discussed the importance of the growth in IP networking Explained common networking protocols such as TCP, UDP, IP, DHCP, DNS, and NAT Selected, installed and configured consumer routers for wired environments Created and implemented IP addressing schemes for connected network devices (computers, AV, lighting, control, etc.) Created system documentation for IP networks 27

28 Questions? Thank You! Please submit course evaluations 7150 Winton Drive Suite. 300 Indianapolis, IN OSI Model Analogy OSI layer Application Presentation Session Transport Network Data link o LLC o MAC Physical Corporate Analogy CEO Lawyer Executive assistant Shipping manager ShipCo dispatcher ShipCo driver/truck o Traffic laws o Traffic lights Road 28