© 2007 Cisco Systems, Inc. All rights reserved.Cisco Public ITE PC v4.0 Chapter 1 1 Connecting to the Network Networking for Home and Small Businesses – Chapter 3
ITE PC v4.0 Chapter 1 2 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Objectives Explain the concept of networking and the benefits of networks. Explain the concept of communication protocols. Explain how communication occurs across a local Ethernet network. Describe Access layer devices and communication methods on a local Ethernet network. Describe Distribution layer devices and communication methods across networks. Plan, implement, and verify a local network.
ITE PC v4.0 Chapter 1 3 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Networking and Its Benefits Define the term network and identify various types of networks
ITE PC v4.0 Chapter 1 4 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Networking and Its Benefits Small home networks connect a few computers together and to the internet Small office/home office (SOHO) networks connect home computers to a corporate network Medium to large networks have multiple locations and hundreds of thousands of computers World Wide networks connect hundreds of millions of computers
ITE PC v4.0 Chapter 1 5 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Networking and Its Benefits Define the components of an Information network Hosts Shared Peripherals Networking Devices Networking Media
ITE PC v4.0 Chapter 1 6 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Networking and Its Benefits Describe the Roles of computers on a network Clients and servers Servers provide a service Web Site FTP Server (File downloads) Clients access services Outlook, Eudora Internet Explorer, Firefox FTP Client, Filezilla
ITE PC v4.0 Chapter 1 7 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Peer-to-Peer Networks Build computer peer-to-peer network and verify Peer-to-peer networks are typically used for 10 or fewer clients
ITE PC v4.0 Chapter 1 8 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Network Topologies Logical topology diagrams include naming and IP address schemes
ITE PC v4.0 Chapter 1 9 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Source, Channel, Destination Source: person with the message Destination: target of the message Channel: voice
ITE PC v4.0 Chapter 1 10 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Rules of Communication Attributes of a communication protocol:
ITE PC v4.0 Chapter 1 11 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Message Encoding Thoughts are encoded into language Language is transmitted to recipient Like language computer data is converted to bits before it is sent over the wire
ITE PC v4.0 Chapter 1 12 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Message Formatting Messages must follow a particular format—like a letter or phone call Messages are encapsulated (addressed) before being sent to the appropriate location On a network messages are formatted into frames
ITE PC v4.0 Chapter 1 13 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Message Size Messages have size restrictions depending on the channel used Messages must be of a particular size Ethernet message sizes are limited to bytes
ITE PC v4.0 Chapter 1 14 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Message Timing Access method Determines when a message can be sent This helps avoid collisions Flow control Determines how much information can be sent at any given time Response timeout Determines what action to take if there is no response in a reasonable time period
ITE PC v4.0 Chapter 1 15 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Message Patterns Unicast: Message to a single entity Multicast: Message to a group Broadcast: Message to everyone
ITE PC v4.0 Chapter 1 16 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Communication Protocols Attributes of a communication protocol: Message format Message size Timing Encapsulation Encoding Standard message pattern
ITE PC v4.0 Chapter 1 17 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Importance of Protocols Network devices must follow the protocols to communicate with one another The Ethernet protocol defines local network communication including message format, message size, timing, encoding, and message patterns.
ITE PC v4.0 Chapter 1 18 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Standardization of Protocols Standards are beneficial to networking in many ways: Facilitate design Simplify product development Promote competition Provide consistent interconnections Facilitate training Provide more vendor choices for customers
ITE PC v4.0 Chapter 1 19 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Standardization of Protocols Example: BASE-T represents the 100 Megabit Ethernet using twisted pair cable standards 100 is the speed in Mbps BASE stands for baseband transmission T stands for the type of cable, in this case, twisted pair
ITE PC v4.0 Chapter 1 20 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Physical Addressing Physical addressing identifies Source, Destination and Channel on an Ethernet Network
ITE PC v4.0 Chapter 1 21 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Ethernet Communication Describe some of the basic characteristics of Ethernet for communicating across the channel
ITE PC v4.0 Chapter 1 22 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Hierarchical Design of Ethernet Networks Access Layer - to provide connections to hosts in a local Ethernet network. Distribution Layer - to interconnect the smaller local networks. Core Layer - a high- speed connection between distribution layer devices.
ITE PC v4.0 Chapter 1 23 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Logical Addressing IP addresses are considered logical addresses IP addresses have a host portion and a network portion Both IP addresses and MAC addresses are required for communication
ITE PC v4.0 Chapter 1 24 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Access and Distribution Layer Devices Switches and hubs are access layer device that allows multiple computers to connect to the network Routers are distribution layer devices that allow multiple networks to communicate with one another
ITE PC v4.0 Chapter 1 25 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Access Layer The access layer allows multiple devices to connect to the network Devices such as phones, printers, computers, servers, etc. all connect at the access layer Hubs and switches are access layer devices
ITE PC v4.0 Chapter 1 26 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Function of Hubs Hubs ONLY broadcast messages Hubs are considered Layer 1 devices (OSI Model)
ITE PC v4.0 Chapter 1 27 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Functions of Switches Switches send unicast messages to the destination Switches learn MAC addresses by “flooding” Switches are Layer 2 devices (OSI Model)
ITE PC v4.0 Chapter 1 28 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Broadcast Messages Broadcast messages allow a host to send a message to all other hosts on the network while sending the message only once The broadcast MAC address is FFFF.FFFF.FFFF If a host sends a message to a hub it is broadcast to all hosts on the network A local network is referred to as a broadcast domain
ITE PC v4.0 Chapter 1 29 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Switch Behavior When a switch receives data from a host with a MAC address not listed in it’s MAC table it adds that address to the table When a switch receives a frame with a destination MAC address not in it’s table it floods the frame to all ports When a switch receives a frame with a destination MAC address in the table, the frame is sent as a unicast
ITE PC v4.0 Chapter 1 30 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public MAC and IP A NIC will only accept a frame if the destination MAC is a broadcast MAC or it is the NICs MAC Most applications rely only on the IP address MAC is determined using address resolution protocol (ARP)
ITE PC v4.0 Chapter 1 31 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public ARP The sender broadcasts a frame including the IP address of the destination All network hosts receive the broadcast, but only the host with a matching IP address responds by sending it’s MAC address back to the sender The sending host receives the message and stores the MAC address and IP address information in the ARP table.
ITE PC v4.0 Chapter 1 32 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Distribution Layer Devices and Communication Methods Broadcast containment Security Locations Logical Grouping
ITE PC v4.0 Chapter 1 33 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Describe the function of routers and how they are used in the network A router connects a network to other networks Routers rely on packets and logical address A packet is the encapsulated data inside a frame
ITE PC v4.0 Chapter 1 34 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Default Gateway Default Gateways allow devices on one network to communicate with another network
ITE PC v4.0 Chapter 1 35 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Routing Tables Routers use IP addresses to determine where traffic should be sent Routers are considered layer 3 devices Routers modify MAC addresses but do not change IP addresses of data passing through
ITE PC v4.0 Chapter 1 36 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Tables Maintained by Routers ARP Tables are used to determine the MAC of the destination Routing tables are used to send traffic out a specific interface Routing tables can be updated dynamically or manually
ITE PC v4.0 Chapter 1 37 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Local Area Network (LAN) A group of local computers or network devices under one administrative control
ITE PC v4.0 Chapter 1 38 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Adding Network Hosts to Local and Remote Networks Locally: just plug in Remotely: requires routing
ITE PC v4.0 Chapter 1 39 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Packet Tracer 5.3 Be sure to do packet tracer activities in the curriculum
ITE PC v4.0 Chapter 1 40 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Plan, Implement and Verify a Local Network Plan and document the building of a small home or small business Ethernet network
ITE PC v4.0 Chapter 1 41 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Plan and Document an Ethernet Network Network planning starts with information gathering: Number of hosts Applications used Sharing and Internet connectivity requirements Security and privacy considerations Reliability expectations Connectivity requirements including, wired and wireless
ITE PC v4.0 Chapter 1 42 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Plan and Document an Ethernet Network Physical environment Temperature control and placement of power outlets Physical configuration Location of routers and switches Device interconnections and cabling Hardware configuration Logical configuration Location and size IP addressing Naming and sharing Permissions
ITE PC v4.0 Chapter 1 43 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Plan, Implement and Verify a Local Network Build a virtual model of their small home or small business network
ITE PC v4.0 Chapter 1 44 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Multi-function Device Multi-function routers include: Router Wireless access point Switch Firewall
ITE PC v4.0 Chapter 1 45 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Connecting the Linksys Router Internet port connects to the Internet Ethernet port connects to the Ethernet
ITE PC v4.0 Chapter 1 46 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Plan, Implement and Verify a Local Network Perform simple workgroup tasks in order to share resources
ITE PC v4.0 Chapter 1 47 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Summary Information networks carry data using hosts as clients, servers, or both. All computer communication involves a source, destination, and channel. Rules called protocols govern computer communications. Larger networks are divided into smaller, more manageable ones using a layered hierarchical design. Each network host needs both a physical MAC address and a logical IP address. Good network design requires a network plan.
ITE PC v4.0 Chapter 1 48 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public