Connecting a router and a switch

Hello, I'm a newbie here.

I just did a virtual lab, in which I connected a Cisco 1900 Switch with a Cisco Router. I pinged it, and it was a successfull connection.

The lab explained everything, except the main idea.
Please bare with me on this question.

Why would I connect a Router and a Switch for ?

I am reading the tech notes provided, but the router and the switch
thingy just boogles my brain.

Thanks,
SiLentThReaD

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Comments

Webmaster

SiLentThReaD wrote:

Why would I connect a Router and a Switch for ?

for several reasons:

The first is the most common:
WAN/Internet

router

switch---clients/hub/switches.

second, which goes for layer 2 and layer 3 switches is to route information between VLANs ("inter-VLAN communication")

Switch(with VLAN 1 and 2)

router

Switch(with VLAN 3 and 4)

I hope this helps!

Are you peparing for Network+ or CCNA?

SiLentThReaD

Yes, I am studying for Network+ exam.

The A+ was easy, because I have a PC at home, and I did all the physical,software upgrading and troubleshooting.

The Network+ is more difficult, since I don't have a spare LAN hanging around.

I bought a Network+ study package which comes with a book, and a virtual lab. The virtual lab is where I did this Cisco config thingy.

Thanks for your help.

I have a few more questions, if that is okay.

1-So, if I only have VLAN1 and VLAN2, I would only need
a router, and not a switch ?
It looks to me like the switch is only needed if there are more
than one local area networks.

2-When the router is used for internet connection, does it directly
connect to the ISP. If this is the case, must it be a static IP ?

Sorry for all the questions

Webmaster

SiLentThReaD wrote:

I have a few more questions, if that is okay.

1-So, if I only have VLAN1 and VLAN2, I would only need
a router, and not a switch ?
It looks to me like the switch is only needed if there are more
than one local area networks.

2-When the router is used for internet connection, does it directly
connect to the ISP. If this is the case, must it be a static IP ?

Sorry for all the questions

Ask as much as you like... that's what these forums are for

1. Actually the router is needed when there are more than 1 LANs (or WANs). The switches are needed to create VLANs... VLANs are optional though, not every switch uses VLANs. If you have two switches with one or more VLANs each you need a router to let them talk to each other. Thus a router can be used to connect LANs (and WANs) as well as Virtual LANs (VLANs)

2. Yes, it connects to the ISP. The IP is usually, but not always static, a router can have an ISDN BRI interface used to dial into an ISP everytime it is needed, in such cases (when the internet connection is dialup and used for outbound access only) the IP address can be dynamically assigned by the ISP. If the router uses a dedicated connection (i.e. leased line or frame relay) the IP is always static.

SiLentThReaD

wow, thanks again. :P

This forums rules.

I will recommend it to my uncle who is also working toward
the Network+.

SiLentThReaD

xrayeyes

You would connect a switch to the router to multiple the number of hosts (devices or users) connecting the network. The hosts use the switch to get to the router. The router acts as the "gateway" to the resources on other networks. Enjoy.

KingK

This is how I am going to network my brothers church.

Say for instance you call Ma Bell for DSL service and get a static IP.

Theres your backbone.

Assign the static IP address to one of the ports on the router. The other port you would assign a gateway address (any addressing scheme on the other side of the router). Say, if its a Router with one Ethernet port (e0)and one serial port (s0), you would assign the ethernet port (e0) the gateway address.

All the machines would connect to the switch and you would connect the switch to the router.

The router acts as a firewall/gateway of sorts and to the internet, they would only see the the static IP assigned to you by your service provider or ICANN. The static address would be assigned to the serial port, in this case (s0).

The switch provides connectivity to all the other computers so they can be on the network at the sametime.

You would connect all the computers to the switch. You would input the gateway address you assigned to the router in the TCP/IP properties.

And there ya go (aside from running the cable and terminating the RJ-45 adapters and configuring IOS on the router and/or the switch.)