Serial Signatory Routing Made Easy

Serial signatory routing

welcome to Train Signal I'm Ross Bogardus and in this video we're going to be diving into router configuration now this is the really cool part of data networking when we get to actually get on the router and start configuring and playing with it the problem is is that the learning curve to this can be a little intimidating at first but what we're going to do is go through step by step make sure you understand exactly how to get on the router and put a base configuration on it so you can actually pass traffic through it so before we get into that though we have to take a look at the router that we're going to be configuring and discuss the interfaces on it and how we connect to it and and whatnot so here in this image I have a cisco 18:41 router this is the router that I'm going to be using to demonstrate all of the router configuration and routing protocols and networking throughout this video series now unfortunately the cisco 18:41 is no longer made but it is an extremely popular router in industry it is in many many many small businesses and in the large business enterprise world they use them there as well for routers at remote sites so if you have a large organization and you may have a remote site in a rural area that's far away chances are you would use a device like this in order to connect that rural site up to the main site of your network let's talk about a couple things here first first let's talk about the cables so the cabling we need to connect our router together is going to be varied based on our configuration but essentially here we're going to need a rollover cable now a rollover cable is a cable used to configure a cisco router it has a very specialized pin setup on it so that we can use it to connect from the router to a serial port of a PC in order to put that base configuration on the router itself second we're going to be cat 5 or cat 6 cables these are just standard Ethernet cables that we're going to connect our router to either a PC or a switch and we may need a cat5 crossover cable or a cat5 straight-through cable it could be one or the other this usb-to-serial adapter or serial to USB adapter what that is is it's a mechanism to put a serial port or an rs-232 port on your laptop which nowadays typically do not come with serial ports now what the heck is a serial port well the serial port is an rs-232 connector it's a very old-school way of doing data networking as a matter of fact if you ever used a modem modems use serial communication to transfer information so if you had that dial-up modem in the mid 90s maybe even in 2000 geez my grandma was using a dial-up modem all the way up until 2007 or so those dial-up modems all used serial communication to connect from the modem itself to the PC and then from the modem out to the telephone network into somebody else's modem those all serial based communication well nowadays we don't use modems most of our devices that we buy PCs laptops and whatnot do not come with a serial port so we have to actually add that serial port in in order to get the functionality on our PC so that we can configure the router or at least put that base configuration on the router now that last cable there is the V dot 35 cable this is used for connections that are like t1 connections t3 connections this V dot 35 cable is an old-school serial cable for high-speed serial networks when do we use that cable well if we have a high-speed serial network like a t1 t1 is operate at 1.5 megabits per second now chances are if you live in a larger city in the United States or Europe or any other larger country that has excellent access to Internet chances are you're a t1 at 1.5 megabits per second is going to be ridiculously slow compared to the other technologies out there like cable modem and DSL so in modern world we don't actually use that vida 35 cable very often as a matter of fact if we do need a t1 connection oftentimes it comes in to our facility with a cable that looks just like this cat 5 cable except it's going to be called a ds1 cable instead of cat 5 so we have lots of options here for our serial communications the reality is is that in order to study for the CCNA you have to understand what these V dot 35 cables are in order to operate networks in the real world we don't use those serial connections as much anymore most of our connections are going to be using this cat5 cat6 type cable and Ethernet as our protocol okay so let's dive into the router then so on the router let's start at the rightmost side here we have the power plug we have the power switch and then we have this slot 0 and slot 1 now the slot 0 and slot 1 these are these module slots and what I have in there right now is the are these cards it's called a 1d su - t1 and what that is it's a serial port that allows us to connect two routers together using something like a t1 connection and I actually have two of those network interface cards these serial network interface cards plugged into slot 0 on the right hand side and slot 1 on the left hand side now these serial cards that I have plugged in here are not the only modules we can plug in there there's a variety of modules we can plug in extra Ethernet ports we can put a little switch in there there's some security modules we can add these slot 0 and slot 1 are modular they're meant for lots of different things I just happen to have mine configured with two serial ports because that's the primary focus of CCNA study now in the middle here there are some built-in ports and the built-in ports there's usually four of them especially on the eighteen forty one and the two on the left are going to be for transferring actual data and those are Fast Ethernet ports fast ethernet operates at a maximum of 100 megabits per second so if we look at the hierarchy actually of the terminology their Ethernet is a 10 megabit per second technology fast Ethernet is 100 megabits per second and Gigabit Ethernet is a thousand megabits per second then it goes up from there and we refer to them accordingly so whenever refer to Ethernet on a Cisco router we're talking about a 10 Meg connection whenever we're talking about fast ethernet we're talking about a hundred Meg connection and Gigabit Ethernet or gig Ethernet or even gig II we're talking about 1,000 megabits per second on this 18:41 we have two fast ethernet ports the fast ethernet port on the bottom is labeled fastethernet 0/0 and the fast ethernet port on the top is labeled fastethernet 0/1 these use these cat 5 or cat 6 cables with an rj45 end right next to it you see two more ports and those two ports look nearly identical to the two ports on the left well these two ports on the right are the console and aux port those are actually not fast Ethernet ports even though they have the same kind of connector they are not fast Ethernet ports so console and aux are not fast ethernet a lot of newbies when they're working with the cisco router they'll actually plug their fast ethernet cable into the console port and try to pass data across it and wonder why it's not working and the big reason there once again is the console port is not a fast ethernet port well the console and aux ports are here are they are used for configuration and on a Cisco router we use serial communication in order to communicate with the router well but wait a minute Ross you just told me we we use serial communication for the T ones yes this is true we use a serial communication to pass data actual routed data with IP addresses and stuff in it and we use that with these serial interfaces the serial network interface cards they're also called LAN interface cards or wicks WIC these cards actually do use serial communication and the neat thing about them is that they can pass traffic at the network layer of the OSI model what that means is that they can actually pass traffic that has an IP address in it the console in the aux port cannot do that well the console in the aux port can only pass data basically at the data link layer and it's meant in order to put a base configuration on our device so these Cisco routers when they come out of the box they are blank there's a default configuration on it but the default configuration is extremely minimal and does not let you operate the router fresh and clean out of the box if you pull that router out of the box plug cables into it and turn it on nothing will happen because all of the interfaces are shut off by default except for the console and aux port which allow you to connect a rollover cable to it plug that into the serial port of your PC or your serial 2 USB adapter and actually use that then to put the base configuration on your device why the aux port then we have the aux port because remember earlier I told you that this device may be sitting in a rural office that may be a hundred and 50 miles away from your desk well we use the aux port there so that we can actually hook up all modem to the aux port and plug it into a telephone line that way if there's some issue where the network goes down at the site where this is located instead of having me to drive in my car drive 150 miles to the site I don't have to do that I can sit at my desk dial in with a modem and I realize modems are antiquated but we actually still kind of use them in data networking for backup support well actually plug that modem right into the aux port of the router then we can dial in and check out what's happening with that router should there be a network into rushon and we cannot reach the router via its IP address so this gives us an out-of-band mechanism to control the router which is really outstanding now the other reason we'd use that aux port and the modem dial-up is sometimes we're configuring stuff on that router and you can actually do something called cutting your arm off which means that you shut the network connection down between your PC and the router when you shut the network connection down between the two devices you can no longer configure the device so you have to have some other mechanism to get into the router and configure it so the console and aux ports are used for configuration our Fast Ethernet ports are used to transfer data that's what we're going to hook up to either a switch or a switch and then a PC so we're going to have basically network devices hanging off of those fast Ethernet ports and then our LAN interface cards here the serial ports these two cards in here we're going to use those to connect to other routers