Packet Tracer Network Simulator (2014)

Chapter 2. Network Devices

Network devices form the core of networking. In this chapter, you'll learn about all of the network devices available in Packet Tracer and the modules used by it. So, after you are done customizing a device with your preferred modules, wouldn't it be nice to save them so that the device is available for use the next time? Don't know Cisco Internetwork Operating System (IOS) commands? After reading the Configuring network device section, you'll be on your feet configuring Cisco routers and switches without using any commands.

Cisco devices and Packet Tracer devices

Selecting Switches or Routers from the device-type selection box lists both Cisco devices and some devices labeled Generic. These are custom Packet Tracer devices running on Cisco IOS, but the slots that hold the modules are different.

Routers

A router provides connectivity between two logical networks. Every router in Packet Tracer can be switched on or off by using the provided power button.

The power switch is required to make a device simulate its real counterpart. Modules can be added or removed only after powering off the device. If the running configuration is not saved, power cycling a device will make it lose its configuration.

The following routers are available in Packet Tracer:

· Cisco 1841: This is an Integrated Service Router (ISR) having two Fast Ethernet ports, two slots for High Speed WAN Interface Cards (HWICs), and one slot for Advanced Integration Module (AIM)

· Cisco 1941: This is similar to the previous model but runs on Cisco IOS Version 15. It has two ports that operate at Gigabit Ethernet speeds.

· Cisco 2620XM: This is a multiservice router with one Fast Ethernet port, two slots for WAN Interface cards, and one slot for AIM.

· Cisco 2621XM: This is similar to the previous model, except that this router has two Fast Ethernet ports.

· Cisco 2811: This ISR comes with two Fast Ethernet ports, four WIC slots, and a dual slot for AIM.

· Cisco 2901: This router has two Gigabit Ethernet ports, four WIC slots, and two Digital Signal Processor (DSP) slots. This router uses Cisco IOS Version 15.

· Cisco 2911: This router has three Gigabit Ethernet ports and all the other features of the previous router. It runs on IOS Version 15.

· Generic Router-PT: This is a custom router running on Cisco IOS. It contains 10 slots and has separate modules with a naming convention beginning with PT.

Switches

A switch, also called a multiport bridge, connects more than two end devices together. Each switch port is a collision domain. The following switches are available in Packet Tracer:

· Cisco 2950-24: This managed switch comes with 24 Fast Ethernet ports.

· Cisco 2950T-24: This switch is a member of the Catalyst 2590 Intelligent Switch family and has two Gigabit Ethernet ports in addition to the 24 Fast Ethernet ports.

· Cisco 2960-24TT: This is another 24 port switch; the previous switch has Gigabit Interface Converter (GBIC) for Gigabit Ethernet ports, whereas this switch has Small Form-factor Pluggable (SFP) modules for the same. Note that this is a difference only on real switches, it has no impact on Packet Tracer.

· Cisco 3560-24PS: This switch is different from the others because it is a layer 3 switch that can be used to perform routing in addition to switching. The PS suffix implies support for Power over Ethernet (PoE), which can be used to power up IP phones without using power adapters.

· Bridge PT: This is a device used to segment a network and it has only two ports (which is why it is a bridge; if it had more, it'd be called a switch).

· Generic Switch PT: This is a Packet-Tracer-designed switch running on Cisco IOS. This is the only customizable switch with 10 slots and several modules.

Like the generic router, the switch section also includes a generic switch with 10 slots that can be customized with the required modules. Except for the generic switch, other Cisco model switches cannot be customized and do not have a power switch. This is because that is how real switches of the same models are designed.

Other devices

Packet Tracer has more than just Cisco routers and switches, which we'll see in this section. These devices do not have any configuration options and work out of the box.

· Hub PT: This network hub was the oldest way to connect multiple end devices together. It still exists in Packet Tracer so that you can simulate and learn about network storms and broadcasts. This Packet Tracer device has 10 slots.

· Repeater PT: This device is used to boost the signal on a wire when the distance between two points is high. We'll be using it in Chapter 5, Navigating and Modifying the Physical Workspace; this device has two slots.

· Coaxial Splitter PT: This is used to split a single coaxial connector into two. It has three coaxial ports and cannot be customized in any way.

Customizing devices with modules

A device module is a piece of hardware containing several device interfaces. For example, a HWIC-4ESW module contains four Ethernet (10 MBps) ports. Similar to a real router/switch, the device has to be powered off in order to add or remove modules.

The power switch is on the right-hand side of each device, with a green LED indicating that the power is on. Click on this switch to turn it off. To add a module, drag one from the modules list and drop it onto an empty slot. If a module doesn't fit into that slot, it automatically returns to the module list.

To remove a module, power off the device and drag it from the slot back to the module list.

Naming convention

Each router has more than a dozen modules but the interface they offer can be identified by their names. So, we have grouped them based on their similarities.

· Copper Ethernet Interface: This is the normal LAN interface, which takes in an RJ-45 connector crimped to a copper cable. Based on speeds, these interfaces are named Ethernet (10 MBps), FastEthernet (100 MBps), and GigabitEthernet (1000 MBps). Modules having Ethernet interfaces can be identified with a number followed by E, FE, CE, CFE, or CGE. Modules with SW provide switching features when used on routers.

· HWIC-4ESW (four Ethernet switching ports)

· WIC-1ENET (single Ethernet port)

· NM-1E (single Ethernet port)

· NM-1FE-TX (single Fast Ethernet port)

· NM-4E (four Ethernet ports)

· NM-ESW-161 (16 Ethernet switching ports)

· PT-ROUTER-NM-1CE, PT-ROUTER-NM-1CFE, PT-ROUTER-NM-1CGE (Packet Tracer custom modules)

· Fiber Ethernet Interface: This is similar to the previous interface, except that it uses a fiber cable. These modules are identified based on the letter F.

· NM-1FE-FX (single Fast Ethernet fiber media)

· PT-ROUTER-NM-1FFE, PT-ROUTER-NM-1FGE (Packet Tracer custom modules)

· Serial Interface: Modules with serial interfaces have the letter T or the string A/S. The difference is that the ones with T are synchronous while the A/S modules are asynchronous. This difference affects only production environments, but in a simulator it makes no difference.

· WIC-1T, WIC-2T (a single or dual synchronous serial port)

· NM-4A/S, NM-8A/S (four or eight asynchronous/synchronous serial ports)

· PT-ROUTER-NM-1S, PT-ROUTER-NM-1SS

· Modem Interface: Modules with this interface have RJ11 ports for analog telephone cables. They are identified by having the letters AM present after a number as shown in the following list:

· WIC-1AM (dual RJ11 ports for phone and modem)

· WIC-2AM, WIC-8AM (two or eight RJ11 ports)

· PT-ROUTER-NM-1AM

· WICs within NMs: Some Network Modules (NM) don't take up all the space of a slot, so they provide WIC slots within them to accommodate smaller cards. Such modules can be recognized by the letter W at the end of their names.

· NM-1E2W, NM-1FE2W (a single Ethernet / Fast Ethernet port and two WIC slots)

· NM-2E2W, NM-2FE2W (two Ethernet / Fast Ethernet ports and two WIC slots)

· NM-2W (no interfaces, only two WIC slots)

· Slot Covers: Packet Tracer also provides covers for empty slots. While it makes no difference in a simulator, it can give a cleaner look when using the physical view (more information on this in Chapter 5, Navigating and Modifying the Physical Workspace).

· NM-Cover: Covers a network module slot

· WIC-Cover: Covers a WIC slot

· HWIC-8A: This module is new to Packet Tracer 6. It provides eight asynchronous EIA-232 connections to console ports. A router can be used as an access server if this module is plugged in.

Creating a custom device

If you require a router with a particular set of modules, it could be a daunting task to drag-and-drop modules each time before creating a topology. So Packet Tracer offers a feature to save a device that you've customized as a custom-made device. Carry out the following steps to create a custom device:

1. Drag-and-drop a network device into the work area. For this example, we'll use a Generic switch: Switch-PT-Empty.

2. Click on the switch to open its configuration dialog box, and turn the device off.

3. Add your most-used modules to this switch.

4. Navigate to Tools | Custom Devices Dialog, or press Ctrl + E.

5. Click on the Select button, and then click on the switch that was just customized.

6. Provide a name and description, and then click on Add and Save.

This custom device is saved with a .ptd extension in %USERPROFILE%\Cisco Packet Tracer 6.0.1\templates\; to make this custom device available to all users, copy it to %PT5HOME%\templates\.

Emulating WAN

To bring in more real-life scenarios, Packet Tracer has devices that emulate a WAN. Clicking on the WAN emulation cloud icon from the device-type selection box lists the following devices:

· Cloud-PT: This device looks like a cloud in the toolbar, but under the configuration window it looks more like a router with several slots. The following modules are available for the cloud device:

· NM-1AM: This module provides an RJ11 connector for connecting modems using telephone cables. The interface name of this module is ModemN, with N being the port number.

· NM-1CE, NM-1CFE, NM-1CGE: These three modules provide an Ethernet, Fast Ethernet, or Gigabit Ethernet interface respectively, through which the devices connected to the modem and cable interfaces can be accessed. Except for speed, all three modules perform the same function.

· NM-1FFE, NM-1FGE: These two modules provide Fast Ethernet or Gigabit Ethernet for connecting fiber media. Functionality-wise, they perform the same function as the previous modules.

· NM-1CX: This module has a coaxial connector for connecting a cable modem.

· NM-1S: A serial port is available on this interface for configuring frame relay. The Config tab for this interface provides options for creating frame relay mappings.

· DSL-Modem-PT: This is a modem with an Ethernet interface and an RJ11 interface. The Ethernet interface can be switched between Ethernet, FastEthernet, and GigibitEthernet. This device doesn't have any configuration options.

· Cable-Modem-PT: This modem is similar to the previous one, except that it supports a coaxial port.

Accessing the CLI

The Command-line Interface of a device in Packet Tracer can be accessed in two ways:

· The CLI tab

· Console port

Although it is possible to access a device through SSH or Telnet, these are Cisco methods and are not exclusive to Packet Tracer.

The CLI tab

This is the simplest way of accessing the Command-line Interface of a device; click on a network device, navigate to the CLI tab, and you'll see the booting process.

The Console port

There is no difference between what is seen and controlled in this method and the previous one, but the Console Port can be used to make the topology look similar to the real world. Follow the steps to configure the console port:

1. Add a PC or a laptop to the workspace.

2. Choose connections, and then click on the console cable.

3. Connect the console cable of the network device to the RS-232 port of the PC/laptop.

4. Open the PC/laptop, navigate to the Desktop tab, open Terminal, and then with the default settings, click on OK to view the console. The following screenshot displays a router's console through its terminal:

In step 2, if you use the Automatically Choose Connection Type option, the Ethernet ports of both of the devices will be connected.

Configuring network devices

In this section, you'll learn how to configure Cisco routers and switches without using a single command! Yes, it is possible; Packet Tracer provides a Config tab that contains GUI options for the most common configurations. What's more, as you tinker with the GUI, its equivalent Cisco IOS command is also displayed. Take a look at the following screenshot:

From the Config tab of the switch, we will set the Interface option to FastEthernet0/1 and uncheck the On checkbox for Port Status. So the Equivalent IOS Commands section displays the following command to achieve this process:

Switch>enable

Switch#configure terminal

Switch(config)#interface FastEthernet0/1

Switch(config-if)#shutdown

Using the Config tab, the following can be configured:

· Global settings

· Routing (on a router and a layer 3 switch)

· VLAN database (on a switch)

· Interface settings

Let's see what options are offered under each of these sections.

Global settings

The first part of Global settings allows you to change the Display name and Hostname of the device. The display name can also be changed by clicking on the name below the device icon. The configuration file for the device can also be saved, erased, or exported for later use.

The Algorithm Settings section contains settings meant for advanced users who want to minutely tweak their device to see how it responds to certain situations. These settings can also be globally set for all network devices by navigating to Options | Algorithm Settings, or by using the shortcut Ctrl + Shift + M.

Routing

This section has options for configuring Static and dynamic routing (RIP). To configure static routing, enter the network address, netmask, and its next hop address, and then click on Add. Here is some sample network information:

· Network: 192.168.30.0

· Mask: 255.255.255.0

· Next Hop: 10.0.0.6

To configure Routing Information Protocol (RIP), it is enough to add only the network IP. Please note that the GUI uses RIP Version 1, so classless routing is not supported. Routing will be discussed in detail in Chapter 6, Configuring Routing with the CLI. Apart from routers, routing can also be configured on the 3560-24PS switch, as it is a layer 3 switch.

The VLAN Database

This section will teach you how to create and remove VLANs. VLANs and trunking are discussed in Chapter 10, Configuring VLANs and Trunks. Only the VLAN database can be modified from these options; adding interfaces to these VLANs is what we'll see in the next section.

Interface settings

This section slightly differs from the switch and the router. Switches have options for modifying the speed and duplex setting and for assigning a port to VLAN. On routers, the VLAN section is replaced by the IP address configuration.

While changing the speed and duplex settings, if you are setting it to anything other than auto, make sure that the settings are the same on both ends. For example, if you set it to 100 MBps on one end and 10 MBps on the other, the link won't come up.

Summary

In this chapter, we learned a lot about network hardware devices and their modules, along with each one's features, limitations, and their naming convention. We have also seen the methods through which the CLI can be accessed. By now, you will have been able to configure these devices with just the GUI. If you are the adventurous kind, go ahead and try creating a simple topology with a couple of routers and PCs residing in different logical networks.

In the next chapter, we'll learn about the end devices available in Packet Tracer. The options in the Config tab of these devices will also be explored. You'll be surprised to see the number of devices available.