Let's talk about different flavours of VWIC cards today . When it comes about VWIC, he 1st things comes into my mind is,
1.What is V in VWIC?
2.Why there are different names VWIC, VWIC2 and VWIC3...? What is 1MFT,2MFT? What is difference between VWIC-2MFT-T1 and
VWIC-2MFT-T1/E1???
V in VWIC signifies VOICE..Wan interface cards .it says "VWIC Cards enable customers to leverage voice over T1 and E1 service"
It's a combination voice and wireless interface card.
Why to go for a wireless interface card right? A VIC does the same thing, but for a telephone.
VWIC would be used on a large corporate network instead of just for regular telephone exchange.
Different VWIC card models mentioned in Table 1. Cisco VWIC2 and VWIC3 Interface Cards
Part Number | Description |
VWIC3-1MFT-T1/E1 | 1-Port 3rd Gen Multiflex Trunk Voice/WAN Int. Card-T1/E1 |
VWIC3-2MFT-T1/E1 | 2-Port 3rd Gen Multiflex Trunk Voice/WAN Int. Card-T1/E1 |
VWIC3-1MFT-G703 | 1-Port 3rd Gen Multiflex Trunk Voice/WAN Int. Card-G.703 |
VWIC3-2MFT-G703 | 2-Port 3rd Gen Multiflex Trunk Voice/WAN Int. Card-G.703 |
VWIC3-4MFT-T1/E1 | 4-Port 3rd Gen Multiflex Trunk Voice/WAN Int. Card-T1/E1 |
VWIC2-1MFT-T1/E1 | 1-Port 2nd Gen Multiflex Trunk Voice/WAN Int. Card-T1/E1 |
VWIC2-2MFT-T1/E1 | 2-Port 2nd Gen Multiflex Trunk Voice/WAN Int. Card-T1/E1 |
VWIC2-1MFT-G703 | 1-Port 2nd Gen Multiflex Trunk Voice/WAN Int. Card-G.703 |
VWIC2-2MFT-G703 | 2-Port 2nd Gen Multiflex Trunk Voice/WAN Int. Card-G.703 |
Difference in terms of features and operations,
VWIC generation 1:
1. VWIC Geneartion1 card supports either T1 or E1 but one cannot use it for dual controller purpose.
2.Cisco 2 port VWIC Geneartion1 card does not give an option to take clock source independently for each port. "clock source line independent"
is not supported.
channel-group 1 timeslots 1-24 speed 64
clock source line independent <<<<<< Not allowed
linecode b8zs
channel-group 1 timeslots 1-24 speed 64
clock source line independent <<<<<< Not allowed
Since independent clock sourcing is not supported, circuit will always be sustainable to clocking Slip sec errors when ever 2 ports are being used for data/Voice applications.Most of the customer came up with this issue and CISCO came up with Generation2 card which address the major independent clocking issue,
VWIC generation 2:
The Cisco 2-port VWIC2 cards can enable each port to be clocked from independent clock sources for data applications. This independent clocking capability is not supported for voice applications or with the Cisco ATM/Voice Advanced Integration Modules (part numbers AIM-ATM, AIM-VOICE-30, and AIM-ATM-VOICE-30).
channel-group 1 timeslots 1-24 speed 64
clock source line independent <<<<<< allowed
linecode b8zs
channel-group 1 timeslots 1-24 speed 64
clock source line independent <<<<<< allowed
However Customers started facing another issue when they use VWIC2
2 ports for both voice and data, they can't use Independent clock source.
pri-group timeslots 1-24 speed 64
clock source line independent <<<<<< Not allowed
linecode b8zs
channel-group 1 timeslots 1-24 speed 64
clock source line independent <<<<<< Not allowed
In this case , Cu comes with same issue, getting Slip sec errors, clocking errors. Earlier Cisco use to suggest, As a design perspective better use 2 ports for data only and use another card for voice , not to get slip errors. In order to support independent clocking for both "Data " and "voice" on same card Generation 3 card has come into picture.
VWIC generation 3:
The Cisco VWIC3 cards are supported only on the Cisco Integrated Services Router (ISR) 1900, 2900, 3900 and 3900E series platforms.
The VWIC3 cards add enhancements to the previous generation VWIC2 cards, including: Enhanced clocking capabilities: The Cisco VWIC3 cards can enable each port to be clocked from an independent clock source for data applications. Data ports can also be clocked independent of voice ports. All voice ports on the card much use the same clock source.Multiple data channel-groups supported per T1/E1 port
pri-group timeslots 1-24 speed 64
clock source line independent <<<<<< allowed
linecode b8zs
channel-group 1 timeslots 1-24 speed 64
clock source line independent <<<<<< allowed
Thus VWIC3 eliminates the clocking issue compeletely.
Now it's time for you to choose which Generation card you would like to
go for your network?
VWIC
VWIC2
VWIC3?
Hope it helps.
Regards,
Jyoti
