Setting up a network over 50 users?

thedrama

Lets assume there is a building. In average there are over 50 users(computers).
These computers do have only standard ethernet adapters not with antennas.
Besides communicating these computers, you need them all access Internet
at the same time.

How many switches? Do i need to place a router along with a DSL modem? Any DHCP server? Should VLAN on switches be implemented ?

What should you suggest?

ehnde

thedrama wrote: »

Lets assume there is a building. In average there are over 50 users(computers).
These computers do have only standard ethernet adapters not with antennas.
Besides communicating these computers, you need them all access Internet
at the same time.

How many switches? Do i need to place a router along with a DSL modem? Any DHCP server? Should VLAN on switches be implemented ?

What should you suggest?

Depends on how many switch ports you have per switch.

A modem only modulates and demodulates from analog to digital and vice versa. Some "dsl modems" have built in layer 3 functionality, but this is typically for residential environments. You may be able to get something like a Cisco ISR that has a slot for a DSL modem.

Depends on your addressing scheme.

VLANs are up to the network admin and the needs of the organization.


Are you really a CCNA, or working on the CCNA?

Monkerz

I'd say, if this is a stand alone installation and this office doesn't need to connect back to a DC via VPN or PIP circuit...

Your needs seem very basic.

Order cable or DSL internet service. Purchase a Cisco 2600 from ebay. Connect the Modem to one of the FastEthernet interfaces on the 2600. Setup the interface as the WAN interface to receive an IP from your provider via the modem and set the interface as outside nat interface. Setup the other FastEthernet interface as the LAN gateway by giving it a private IP address and setting it as the inside nat interface. Create a default route to the provider facing interface. Create an ACL allowing all addresses from your LAN, for use with PAT. Setup PAT utilizing the internet facing interface's DHCP address assigned by the provider. Create the local LAN DHCP pool on the router.

Purchase two 48 port 3300 series Dell PowerConnect switches (CHEAP), stack the switches, assign a management IP to vlan 1 that is within the subnet of the gateway IP you assigned to the router earlier, uplink the stacked switch to the LAN interface of the router.

Keep in mind, this is just a quick cheap suggestion. I do not know how much money you are wanting to pour into this.

thedrama

ehnde wrote: »

Depends on how many switch ports you have per switch.

A modem only modulates and demodulates from analog to digital and vice versa. Some "dsl modems" have built in layer 3 functionality, but this is typically for residential environments. You may be able to get something like a Cisco ISR that has a slot for a DSL modem.

Depends on your addressing scheme.

VLANs are up to the network admin and the needs of the organization.


Are you really a CCNA, or working on the CCNA?

Yeah, im a CCNA. But, i had never any opportunity to establish a network, i mean design. What i did only was studying and making knowledges better. I just thought of this design.

Furthermore, my mind was confused about whether using a router or not. Why? Cos, i had run a single-Ethernet port linksys DSL modem in order to access the Internet without taking advantage of a router "even though modems are just used for signal translation".

I know routers are for routing services and connecting "different" networks together. But, isn't it weird to connect one PC to the Internet without a router?(if this is the task of a router)

It is certain that i need a dsl modem or a router which supports DSL interface in order to access the Internet but when sharing?

How about this design ; your network consists of 50 users at least. You need 3-4 layer 2 switches for enough port. Then linked them to a modem, in that case can't i share Internet connection and why not?

ehnde

Sorry if I came off as rude. You would need a router to support 50 users, because more than likely you'll only be using 1 public IP address. You will have to translate the 1 public IP to 50 private ones with nat and a private address range.

thedrama

ehnde wrote: »

Sorry if I came off as rude. You would need a router to support 50 users, because more than likely you'll only be using 1 public IP address. You will have to translate the 1 public IP to 50 private ones with nat and a private address range.

OK, but that modem supported PAT too. What im trying to learn here mainly are two things; one, can't i connect at least 50 computers to the modem
through several switches if that modem supports PAT, DHCP server feature?
(without a router)

two, VLAN case. I know what VLANs do. Their main purposes are two things and These are creating separate broadcast domains/logical subnetworks(preventing high broadcast traffic) with providing security. (implementing different VLANs to switch ports). In such a network design, should i?

capitanuionut

thedrama wrote: »

OK, but that modem supported PAT too. What im trying to learn here mainly are two things; one, can't i connect at least 50 computers to the modem
through several switches if that modem supports PAT, DHCP server feature?
(without a router)

two, VLAN case. I know what VLANs do. Their main purposes are two things and These are creating separate broadcast domains/logical subnetworks(preventing high broadcast traffic) with providing security. (implementing different VLANs to switch ports). In such a network design, should i?

Also Vlans are used to separate different groups of users...if you configure Vlans and put some users in different Vlans you will need a router for inter-vlan communication..

If your modem know PAT and you don't need other things that a router can give you...like Access lists for example than you can go with the modem...

pham0329

thedrama wrote: »

OK, but that modem supported PAT too. What im trying to learn here mainly are two things; one, can't i connect at least 50 computers to the modem
through several switches if that modem supports PAT, DHCP server feature?
(without a router)

Unless the modem also does routing, probably not. Don't you have a network at home? How do you connect to the internet? Chances are, you have a bunch of PC, going to a switch (or a DLINK or Linksys router), that does NAT/PAT/DHCP, which then connects to a modem, which converts those signals and send it off to your ISP.

two, VLAN case. I know what VLANs do. Their main purposes are two things and These are creating separate broadcast domains/logical subnetworks(preventing high broadcast traffic) with providing security. (implementing different VLANs to switch ports). In such a network design, should i?

We wouldn't be able to answer that without knowing what your network requires. Also, I'm sure you're aware since you are a CCNA, but if put your hosts in separate VLAN, you need a L3 device to route between them. This may be a problem if you opt for a cheap DLink or consumer grade router that doesn't support VLAN.

thedrama

You're right. I forgot that. for inter-vlan(different vlan's) communication i need a router.

Still, if we imagine the first thing, without applying a router, isn't it possible to
link computers through a switch to a DSL modem?

bigmantenor

thedrama wrote: »

Furthermore, my mind was confused about whether using a router or not. Why? Cos, i had run a single-Ethernet port linksys DSL modem in order to access the Internet without taking advantage of a router "even though modems are just used for signal translation".

I know routers are for routing services and connecting "different" networks together. But, isn't it weird to connect one PC to the Internet without a router?(if this is the task of a router)

Most consumer-level modems are actually all-in-one devices, combining the functionality of a modem, router, and possibly other devices (switch, wireless AP, etc.). Sounds like the Linksys modem that you are speaking of is actually an all-in-one device, in which case you WERE using a router to connect the PC to the Internet. You have to understand that when studying for the CCNA, many things are simplified to an extent that does not mirror real life. For example, there was a conversation the other day in this forum about inter-VLAN communication, where someone was talking about how you have to have a router in order to communicate between VLANs. This is not actually true: To communicate between VLANs, you need a Layer 3 device, which could be a router or a Layer 3 switch. For the CCNA, most people only learn about the router in this case.

As far as segmenting the broadcast domains by using VLANs, it depends on the needs of your company. You seem to have a good grasp on why someone would want to institute VLANs, so now you would apply that knowledge to the real world. Perhaps one segment of your company requires a higher level of security, so you would throw them in their own VLAN to help keep their traffic separate.

thedrama

bigmantenor wrote: »

Most consumer-level modems are actually all-in-one devices, combining the functionality of a modem, router, and possibly other devices (switch, wireless AP, etc.). Sounds like the Linksys modem that you are speaking of is actually an all-in-one device, in which case you WERE using a router to connect the PC to the Internet. You have to understand that when studying for the CCNA, many things are simplified to an extent that does not mirror real life. For example, there was a conversation the other day in this forum about inter-VLAN communication, where someone was talking about how you have to have a router in order to communicate between VLANs. This is not actually true: To communicate between VLANs, you need a Layer 3 device, which could be a router or a Layer 3 switch. For the CCNA, most people only learn about the router in this case.

As far as segmenting the broadcast domains by using VLANs, it depends on the needs of your company. You seem to have a good grasp on why someone would want to institute VLANs, so now you would apply that knowledge to the real world. Perhaps one segment of your company requires a higher level of security, so you would throw them in their own VLAN to help keep their traffic separate.

That's literally correct. CCNA knowledge doesn't exactly reflect the real-life.
Nevertheless, there are many type of devices which are all built -in nowadays.For example Cisco routers have been taught us are incredibly powerful devices compared to SOHO equivalents.Thats why, suitable devices
depend on the size/type of a network. What i mentioned as a modem was just a linksys DSL modem that comes with a single Ethernet port. My current device at home is an all built- in WAG120n modem/router. I am able to link two laptops wirelessly together also access the Internet.(share it also)

Lets say, i implemented VLAN for special people. (i.e.managers) and i need
router for that kind of network. But, if i did otherwise(no VLAN), was it
possible to connect computers to the modem without placing a router?

pham0329

it would depends on the capability of the modem. If it does NAT/PAT, routing, dhcp then yes.

bigmantenor

thedrama wrote: »

That's literally correct. CCNA knowledge doesn't exactly reflect the real-life.
Nevertheless, there are many type of devices which are all built -in nowadays.For example Cisco routers have been taught us are incredibly powerful devices compared to SOHO equivalents.Thats why, suitable devices
depend on the size/type of a network. What i mentioned as a modem was just a linksys DSL modem that comes with a single Ethernet port. My current device at home is an all built- in WAG120n modem/router. I am able to link two laptops wirelessly together also access the Internet.(share it also)

Lets say, i implemented VLAN for special people. (i.e.managers) and i need
router for that kind of network. But, if i did otherwise(no VLAN), was it
possible to connect computers to the modem without placing a router?

You need a router to communicate between networks/subnets. I'm having a hard time following your question at this point.

thedrama

bigmantenor wrote: »

You need a router to communicate between networks/subnets. I'm having a hard time following your question at this point.

Thats theoretically true. But, what im stuck is you can connect a private
network to the Internet and reverse. Your PC communicates with other PCs with a modem.

Should i think that modem does this because it has routing capability?

VAHokie56

thedrama wrote: »

Thats theoretically true. But, what im stuck is you can connect a private
network to the Internet and reverse. Your PC communicates with other PCs with a modem.

Should i think that modem does this because it has routing capability?

Are you asking if you set up something like this...

{modem-dhcp}---> [switch-vlan1]-->(PC's)

will the PC's then be able to get to the internet? Sorry I am having trouble grasping what your question is

thedrama

VAHokie56 wrote: »

Are you asking if you set up something like this...

{modem-dhcp}---> [switch-vlan1]-->(PC's)

will the PC's then be able to get to the internet? Sorry I am having trouble grasping what your question is

Yeah, so?

VAHokie56

uh yeah so that is your question? If that's what you are asking then all the PC's connected to switch will request dhcp and it will be up to the provider how many it will lease out. If you do that however you would have to blow away any and all private addressing and all your PC's would have public addresses, I am sure you would not want that for a office environment. Once again thought I have no idea what you are asking so I took a shot in the dark.

Edit.
This is assuming your cable modem is handing out DHCP and your company did not pay for a static...

thedrama

Forget all i explained you before. I'll try to tell in a different aspect.

There should be over 50 users/computers (No wireless connection is made)
There should be layer 2 switches in order for these computers to attached to.
These clients should access the Internet simultaneously
There should be a DSL modem for Internet connection.
Modem has PAT feature for private addresses to public match. Also DHCP server feature to assign IP addresses to hosts automatically. Last one, routing capability.

In that case, should i "also" place a router? and why?

VAHokie56

thedrama wrote: »

Forget all i explained you before. I'll try to tell in a different aspect.

There should be over 50 users/computers (No wireless connection is made)
There should be layer 2 switches in order for these computers to attached to.
These clients should access the Internet simultaneously
There should be a DSL modem for Internet connection.
Modem has PAT feature for private addresses to public match. Also DHCP
to assign IP addresses to hosts automatically.

In that case, should i "also" place a router? and why?

If the modem is handling NAT and DHCP for the LAN then NO there is no need for it. If it was me I would not put my trust in a Modem/router from the ISP for a office with 50 end user devices but I realize your not asking for my opinion

thedrama

VAHokie56 wrote: »

If the modem is handling NAT and DHCP for the LAN then NO there is no need for it. If it was me I would not put my trust in a Modem/router from the ISP for a office with 50 end user devices but I realize your not asking for my opinion

You can share what you would do.

pham0329

thedrama wrote: »

You can share what you would do.

I think everyone here have already told you what they would do....they would have a router in between.

Modem -> Router -> Switch -> devices

1) If you're using the ISP's modem for routing/nat/dhcp/firewall, if you switch service, you'd have to recreate the entire configuration.

2) Most ISP won't give you total access to their device, meaning you won't have the level of control as you would with your own device.

3) I'm a little paranoid and don't want my router's config to be accessed by my ISP.

VAHokie56

pham0329 wrote: »

I think everyone here have already told you what they would do....they would have a router in between.

Modem -> Router -> Switch -> devices

1) If you're using the ISP's modem for routing/nat/dhcp/firewall, if you switch service, you'd have to recreate the entire configuration.

2) Most ISP won't give you total access to their device, meaning you won't have the level of control as you would with your own device.

3) I'm a little paranoid and don't want my router's config to be accessed by my ISP.

This about sums it up... Just request a bridged modem with a static IP. Get your self a decent router assign that static IP to your WAN interface of your router. Set up NAT and DHCP then assign a gateway to you LAN interface and cram your switch on it...that gives you one flat local network but you also have the flexabilty to grow should you desire.

bigmantenor

thedrama wrote: »

Yeah, so?

The sarcasm is unnecessary. We are having a difficult time understanding your question, partially due to some level of language barrier I'm sure. When I ask for help with something, I tend towards humility, not arrogance.

MAC_Addy

thedrama wrote: »

Yeah, im a CCNA.

I don't mean to be rude, but if do have the CCNA cert then you need to go back to the drawing board. The CCNA teaches you from basic networking to remote networking. By the looks of things you probably did a **** on this certification and obviously didn't actually learn anything.

thedrama

MAC_Addy wrote: »

I don't mean to be rude, but if do have the CCNA cert then you need to go back to the drawing board. The CCNA teaches you from basic networking to remote networking. By the looks of things you probably did a **** on this certification and obviously didn't actually learn anything.

Maybe you're right maybe wrong. It depends on how you are taught. I took
CCNA course two times.First time, it consisted of just slideshow and couldn't
offer me significant things. But second time, i had gears/tools to practice. I also build network topologies on my own at Cisco packet tracer from basic routing, subnetting to frame relay networking. Used secureCRT, putty
also hyperterminal.

My questions might not probably be understood due to language barrier. But,
there is a certain part here and it is that i struggle too much in order to advance.

Let's get back to my question again,

I know what layer 2 switches are capable of, also routers and many things
from data encapsulation to WAN technologies. However, real-life is a bit different(than theory)

I established a switched computer network with 50 clients. After that, should
i use a DSL modem only or is a router needed additionally?[in order to
share Internet connection]

xenodamus

pham0329 wrote: »

I think everyone here have already told you what they would do....they would have a router in between.

Modem -> Router -> Switch -> devices

1) If you're using the ISP's modem for routing/nat/dhcp/firewall, if you switch service, you'd have to recreate the entire configuration.

2) Most ISP won't give you total access to their device, meaning you won't have the level of control as you would with your own device.

3) I'm a little paranoid and don't want my router's config to be accessed by my ISP.

I agree as well.

You COULD do it with just the box from your ISP, but with 50 users I would install a router and managed switch so you have the capability to grow and expand, in addition to having more control over your network.

danielno8

thedrama wrote: »

Maybe you're right maybe wrong. It depends on how you are taught. I took
CCNA course two times.First time, it consisted of just slideshow and couldn't
offer me significant things. But second time, i had gears/tools to practice. I also build network topologies on my own at Cisco packet tracer from basic routing, subnetting to frame relay networking. Used secureCRT, putty
also hyperterminal.

My questions might not probably be understood due to language barrier. But,
there is a certain part here and it is that i struggle too much in order to advance.

Let's get back to my question again,

I know what layer 2 switches are capable of, also routers and many things
from data encapsulation to WAN technologies. However, real-life is a bit different(than theory)

I established a switched computer network with 50 clients. After that, should
i use a DSL modem only or is a router needed additionally?[in order to
share Internet connection]

Yes it is

gosh1976

when would an ISP send out a business customer a DSL modem that's not really a multifunction device? I mean unless they have a bunch of overstock of Alcatel Speed Touch USB modems left over from 10 years ago!

That being the case than yes I suppose you could just plug a couple switches in and people would be up and surfing.

Bl8ckr0uter

gosh1976 wrote: »

when would an ISP send out a business customer a DSL modem that's not really a multifunction device? I mean unless they have a bunch of overstock of Alcatel Speed Touch USB modems left over from 10 years ago!

That being the case than yes I suppose you could just plug a couple switches in and people would be up and surfing.

This is what I was thinking as well.


Modem/Router/ISP Device >>> Layer 3 Switches>>Access Switches>
(if he needs Intervlan traffic, he can do it with a 3550 or something).

Mind you that this would be less than ideal for security but doable. Not very scalable in terms of handling dhcp and dns either.


My suggestion would be for you to get a decent firewall, either something opensource like pfsense, or a cheap UTM appliance like a Sonicwall. Put that directly behind the ISP device. Do all of your security configurations on that device (IDS/IPS, Firewalling maybe even content filtering and etc). Grab a layer 2, 3 gigabit switches to do your vlanning and VACLS as well as access layer, sort of a smashed core designed. Put a DHCP server on your lan as well as a DNS server (these can be the same box). If you are a windows shop, look at the possibility of using a Domain Controller, if not, look at openldap and bind.

What are the requirements of the network? Wireless? VOIP? Email? Internet Access? File sharing? CRM? Websites? OWA? VPN access? Etc..These are things you need to think about if you are designing a network, it is more than just routers and switches, certainly at the SMB level where one person might do it all. Make sure you can get all of their needs before you start planning. And no all things will not be solved by Cisco gear, you can mix and match. Get cisco where it counts (core and maybe switches) but it would be ok for you to get a WAP that isn't cisco or run asterix instead of call manager. These are things that happen in the real world.

danielno8

gosh1976 wrote: »

when would an ISP send out a business customer a DSL modem that's not really a multifunction device? I mean unless they have a bunch of overstock of Alcatel Speed Touch USB modems left over from 10 years ago!

That being the case than yes I suppose you could just plug a couple switches in and people would be up and surfing.

Thing is the guy stated it was a DSL modem only.

Obviously in real life none of this applies.

Bl8ckr0uter

danielno8 wrote: »

Thing is the guy stated it was a DSL modem only.

Obviously in real life none of this applies.

What's the model number of the device and who is the provider?