Difference between serial & ethernet interface.

[sathyasav]

Hi every one,

i have some doubts in basic stuffs.

Q1: What are the differences between serial interface and ethernet interfaces.

Q2: Can we use ethernet interfaces to terminate WAN connectivity just like serial.Why always we are using serial interfaces to connect the WAN.

Please help me out by answering these questions.

!!!!THANKS IN ADVANCE!!!!!

[Javi Benito]

Hi,

Serial interfaces are used by ISP to provide WAN connections as a frame relay, T1, T3, etc. The port used is V.35 or RS232.

Ethernet interfaces are used in LAN and WAN connections (RJ45). Recently I´ve changed two serial lines by 2 ethernet lines. I think these lines can offer better performance. Apart of this, in my country, month quota is cheaper than Serial line.

regards,

[sathyasav]

Thanks Javi for your reply as a first person.And so only ISP will use serial interfaces for providing WAN connections.But we are using serial interfaces of our routers for connecting WAN at the same time some locations we are using ethernet interfaces for WAN.so what difference it will make.Please elaborate.....

[NAVIN PARWAL]

Hi ,

Serial Interface is generally based on TDM and for any speed which are less than T1/E1 , it genenally works out to be feasible to go for TDM links in which the termination is done on V.35 or G.703 interface .

For higher speed links it is generally feasible to go for Fast Ethernet Links .

It is very country and Telco specific , in certain developing coutnries , you may not find the infrastructure for Fast Ethernet , hence E1 may be the only option.

There are some differences on the capabilities for these two interfaces , some differences which I can briefly highlight are Dynamic BW is easily provided on TDM as compared to Fast Etherent .

Fast Etherent is highly and easily scalable upto 100 MB , after which you require Gig Ethernet Access .

regards

[FirstFoot]

Hi There,

   Good explanation by Navin.

   On top of that, Serials are by nature flexible and it can be comfortably devided like per customer or provider needs from T1 or E1 connection.

   So the Bandwidth allowed to have physical pipe can be clearly configured and adjusted because of TDM structure each T1 or E1 is multiples of 64 kbps slots ( example :- 64 x 32 fpr E1 which 2048 Kbps or 2 Mb circuit) same follow for T1. This is good to have exactly what we run when designing Layer 3 Routing, so Routing protocols can take Routing decisions based on Bandwidth provisioned automatically or adjust with Policy based Routing.

   When it comes to FastEthernet the original build was for LAN connectivity. Of course we can use for MAN or WAN because of multilayer aware of transmissions capability is already rocking in Market. Because of Switching and Routing enhancements ( merge ) and many devices are aware of Layer 2 to 7 traffic patterns in many vendors. So it is difficult to clearly define the scope for these two types these days.

   Hope you got some clarification !

   Happy Reading

[sathyasav]

Hi Ganga & Navin,

Thanks for your reply on this.i got some knowledge by reading your answers.so if we are connecting the WAN or MAN link with the bandwidth more capacity more than T1 and E1 speed,fast  ethernet is a only option..my understanding from your reply

One more question,

  In my company,we have got 20Mb N-mpls links and in some locations we have terminated the links on router Fe interface and in some locations we have terminated in switch FE interface.what differece it will make? Can some one share their idea please?

[NAVIN PARWAL · Accepted solution]

Hi ,

Fast Ethernet is one of the option for any speed above T1/E1 , other TDM options which can be offered are DS-3 and STM1 which can be offered on sub-rated basis as well. For example you can subscribe for 10 MB BW on 45 MB Access .

The answer for your second question , is that there could be a possibility that you have subscribed for L2 VPN (EVPL or VPLS ) or L3 VPN (MPLS ) .

L2 VPN woks on VLAN tags and L3 VPN termiantes on a L3 device.

regards

Navin Parwal

[sathyasav]

Eventually i understood the diff...Thanks guys...

[FirstFoot]

That's good 

[KushalBhetuwal57500]

is this rocket science?what kind of answer are you providing? Didn't get anything-

[stim4967]

Serial interface is totally different from Ethernet. You may share or convert your serial device to Ethernet network with the software - https://www.eltima.com/serial-ethernet-converter/

Or use the hardware converter like Perl or smth. 

[sudheerkumar9@hotmail.com]

When we change the link from Serial to Ethernet, Can same Crypto map config use ?

Hi , We have a serial link with Crypto configured.

Not Telcom wants to change the interface to Etherenet.

There is G0/0 interface . They said new link is MPLS.

Diginet to EThernet .

 Please advise about crypto config . can I use the same Crypto

Current Int

interface Serial0/1/1
 
 description 128k MediaRing/NTT MPLS
 ip address
 ip access-group 101 in
 no ip redirects
 no ip unreachables
 no ip proxy-arp
 ip flow ingress
 encapsulation ppp
 load-interval 30
 crypto map Crypto-map
 
- Can we use below config for Etherenet
interface GigabitEthernet0/0

 description ## CONNECTED TO MPLS ##

 ip address
 ip access-group 101 in

 no ip redirects

 no ip unreachables

 no ip proxy-arp

 ip flow ingress

 ip flow egress

 load-interval 30

 duplex full

 speed 1000

 crypto map Crypto-map

[NATALYATOCHE06133]

thanks!! ,one question ,  I want to simulate in GNS3 the interface 10GE (as i used to see in my work:

TenGigE0/5/1/2 is up, line protocol is up

  Interface state transitions: 129

  Hardware is TenGigE, address is 40ce.2452.8b06 (bia 40ce.2452.8b06) ).

For that i choose GigabitEthernet but i think that the only way can be changing the speed ?