The MPLS-OPS Archive[Date Prev][Date Next][Thread Prev][Thread Next] [Date Index][Thread Index][Author Index][Subject Index] Re: RE: Circuit Emulation using MPLS?
hai , can u suggest me a good link where can i start the g-mpls preperatory stuff, thanks in advance, Ganesh On Tue, 11 Dec 2001 Young, David J wrote : > Thanks to all who commented on this subject. My main > issue is more of a > business issue than technical in than we are an > wholesale only "Access > Service Provider" and do not sell solutions direct to > customers. Therefore > we do not often get involved in changing the customers > network design (i.e. > putting in Media gateways, etc.). We currently have an > ATM network and > offer two main product types... > > 1. IP > 2. TDM > > With TDM, we do Circuit Emulation as it is much easier > for us to just say > "Here is an E1 pipe, use it for whatever you want". > > I have just found a proposed internet draft > [draft-malis-sonet-ces-mpls-05.txt]. I have not read > it though yet but > would be interested in any industry views on this draft > or any other > potential solutions. > > Many thanks, > > David Young > > -----Original Message----- > From: Mathew Lodge [mailto:mathew@cplane.com] > Sent: 10 December 2001 20:54 > To: Santiago Alvarez; raszuk@cisco.com > Cc: Young, David J; 'mpls-ops@mplsrc.com'; > saalvare@cisco.com > Subject: Re: Circuit Emulation using MPLS? > > > At 01:17 PM 12/7/2001 -0800, Santiago Alvarez wrote: > >Let me add some comments. You're effectively providing > circuit emulation > >when you trunk voice through an IP/MPLS network. In > this case, it's > >really the voice gateway the one that compensates for > the jitter and > >possible loss introduced by the network. As Robert > mentioned, the apps > >are been built to connect to the IP/MPLS network and > take care of the > >emulation. I guess if you consider the case of a > network with edge LSRs > >also acting as voice gateways, you could argue that > your MPLS network is > >providing circuit emulation (at least for your voice > services) ;-) > > While this is true, there are a lot of n rvices carried over > voice bearers today that make this an unusable solution > for a carrier-class > network. Good examples are modem and fax traffic. While > both of these can > be jitter buffered, treating them "just like voice" > (e.g. by sticking the > TDM frame into an RTP packet and crossing your fingers) > doesn't work. The > problem in real networks is packet loss. Even very > small amounts of packet > loss on the path (less than 1%) will cause fax and > modem calls to fail when > carried as VoIP. And real networks have enough packet > loss to lead to major > drops in call success rate for fax and modem calls. > > So, what this really means is that it is a combination > of a well engineered > MPLS network and a good IP media gateway that is > required to match ATM > circuit emulation. The MPLS network has to offer > guaranteed bandwidth > (which, by the way, is entirely possible using policing > and marking at the > edge (i.e. int-serv) mapping to coarse grained > diff-serv in the core). The > media gateway has to take care of jitter buffering and > encoding for voice, > fax, modem and any other non-voice traffic carried over > voice-like bearers. > > Regards, > > Mathew > > > >SA > >-- > > > >Robert Raszuk wrote: > > > > > > I think that providing circuit emulation over IP or > MPLS/IP networks > > > should be simply forgotten. If ATM remains alive it > is for this very > > > application. To really provide this over IP you > would need to use RSVP's > > > int serv model what as you know never scaled to the > production > > > capacities of any service provider. > > > > > > With L2 transport or with L3 routing you can achive > achive almost the > > > same set of applications VoIP, videoconferecing etc, > trunking what you > > > would use circuit emulation but this is different - > those new end > > > systems and applications are desiged to work over > IP networks. > > > > > > Old fashined devices desined on are not. > > > > > > Also you should not be mistaken about differences > of carrying ATM cell > > > payload of AAL5 mostly used for data communication > over IP/MPLS networks > > > and trying to carry in the same way AAL1 (circuit > emulation ATM > > > adaptation layer). > > > > > > Rgs, > > > R. > > > > > > > "Young, David J" wrote: > > > > > > > > Can anyone please post any detail relating to > comparison of ATM > Circuit > > > > Emulation Services, Vs capabilities with MPLS to > achieve similar > results. > > > > > > > > Many thanks, > > > > > > > > David J Young > > > > Manager, Voice & Data Services > > > > > > > > Bulldog Communications Ltd > > > > Golden Cross House > > > > 8 Duncannon Street > > > > Strand > > > > London, WC2N 4JF > > > > > > > > Direct line: 020 7484 5644 > > > > Direct Fax: 020 7484 8701 > > > > Mobile No.: 07767 793636 > > > > E-Mail: davidjyoung@bulldogcommunications.- > com > > > > www.bulldogcommunications.com > > > > > > > > **************************************************- > ******************** > > > > This email and any files transmitted with it are > confidential and > > > > intended solely for the use of the individual or > entity to whom they > > > > are addressed. If you have received this email in > error please notify > > > > the system manager. > > > > > > > > This footnote also confirms that this email > message has been swept by > > > > MIMEsweeper for the presence of computer viruses. > > > > > > > > www.mimesweeper.com > > > > **************************************************- > ******************** > > > > Bulldog Communications Limited is registered in > England, number > 4005262, > > > > with its office address at Golden Cross House, 8 > Duncannon Street > > > > LONDON, WC2N 4JF, United Kingdom > > > > > > > > ------- > > > > The MPLS-OPS Mailing List > > > > Subscribe/Unsubscribe: > http://www.mplsrc.com/mplsops.shtml > > > > Archive: http://www.mplsrc.com/mpls-ops rchive.sh- > tml > > > > > > ------- > > > The MPLS-OPS Mailing List > > > Subscribe/Unsubscribe: http://www.mplsrc.com/mplsop- > s.shtml > > > Archive: http://www.mplsrc.com/mpls-ops_archive.shtm- > l > > > >-- > >-------------------------------------------------------- > ---------------- > > Santiago Alvarez (408)527-9285 > : : > > IOS Technical Marketing - MPLS/QoS > santiago@cisco.com ..:::..:::.. > >-------------------------------------------------------- > ---------------- > > > >------- > >The MPLS-OPS Mailing List > >Subscribe/Unsubscribe: http://www.mplsrc.com/mplsops.s- > html > >Archive: http://www.mplsrc.com/mpls-ops_archive.shtml > > | Mathew Lodge | mathew@cplane.com | > | Director, Product Marketing | Ph: +1 408 789 4068 | > | CPLANE, Inc. | http://www.cplane.com | > > > ********************************************************- > ************** > This email and any files transmitted with it are > confidential and > intended solely for the use of the individual or entity > to whom they > are addressed. If you have received this email in error > please notify > the system manager. > > This footnote also confirms that this email message has > been swept by > MIMEsweeper for the presence of computer viruses. > > www.mimesweeper.com > ********************************************************- > ************** > Bulldog Communications Limited is registered in England, > number 4005262, > with its office address at Golden Cross House, 8 > Duncannon Street > LONDON, WC2N 4JF, United Kingdom > > ------- > The MPLS-OPS Mailing List > Subscribe/Unsubscribe: http://www.mplsrc.com/mplsops.sh- > tml > Archive: http://www.mplsrc.com/mpls-ops_archive.shtml ------- The MPLS-OPS Mailing List Subscribe/Unsubscribe: http://www.mplsrc.com/mplsops.shtml Archive: http://www.mplsrc.com/mpls-ops_archive.shtml |
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