Ethernet Frame Overhead Due To Encryption
Jun 24, 2012Ethernet frame overhead due to encryption protocols used, and how can it be resolved?
View 1 RepliesEthernet frame overhead due to encryption protocols used, and how can it be resolved?
View 1 RepliesHow to reconcile what I've observed on our routers on a tunnel interface. The maximum amount of data I can get across the tunnel is 1339 bytes, which seems just a little bit too small. Background: we have two 3845 routers with IOS 12.4(3a) advanced ip services. I have tunnel interfaces on both routers, interface configs are below.
crypto ipsec transform-set MY_TSET esp-3des esp-sha-hmac comp-lzs crypto ipsec profile MY_VTIset transform-set MY_TSET
[ Code]..
When I test the mtu of the source destination interfaces I get 1500 bytes, as you would expect from an Ethernet connection to a service providers MPLS network. See output below:
Router1#ping ip 10.252.0.18 df-bit size 1500
[Code]...
When I test the mtu of the tunnels I get 1339 bytes, see the output below.
router1#ping ip 10.1.40.133 df-bit size 1340
Type escape sequence to abort.Sending 5, 1340-byte ICMP Echos to 10.1.40.133, timeout is 2 seconds:Packet sent with the DF bit setM.M.MSuccess rate is 0 percent (0/5)
[Code]...
That comes to a total of 1420, which is 80 bytes short of the mtu of the source/destination interface of the tunnel.
I've heard that a method to optimize traffic is to use variable length packets. They say that the worst case is in minimum length packet (64 bytes). But I can't understand why.
View 2 Replies View Relatedi want to know that how can i send more than 1506Bytes in payload of ethernet frame insteadd of 1500Bytes(max size)? i have hardware device that can send variable length payload so what changes can be made for this operation
View 6 Replies View RelatedI would like to configure Ethernet jumbo frame setting in a C6509E switch with WS-X6548-GE-TX and WS-X6516A-GBIC port modules, and IOS 12.2(33)SXJ1. whether any of these modules can support jumbo ethernet frames up to 9000 per port bases.Also, if none of these modules support port-based jumbo frame MTU then would the switch allow jumbo frames on Ethernet trunks from an access switch (say a C3560)?
View 3 Replies View RelatedWe're installing ASR1000 series (ASR1001 and ASR1006) routers on a new WAN and have a requirement to enrypt the traffic between the EIGRP neighbors. Each ASR will be connected to the MOE with a gig interface and we will be using L3 on the interfaces with EIGRP as the routing protocol. We have advipservices-k9 IOS-XE
The ASR1006 is our datacenter WAN router and all remote sites have the ASR1001s. The ASR1006 WAN interface will be configured with L3 subinterfaces, one to each remote location, using a /30 mask.
What is the best method to encrypt the traffic between the ASR1006 WAN interface and the remote ASR1001 WAN interface?
We are looking for a solution to avoid VPNs to encrypt data between HQ and Bldgs (point-to-multipoint) Gigabit fiber(untrusted media).Is there any cisco's product providing layer2 encryption over Giga fiber?The HQ has a 6509s and remote bldgs have mixed of 3750s,4500s in trunks.
View 2 Replies View RelatedNetwork is 10.254.0.0/16
snag.gy/3Y8aN.jpg This is the network image.
This is my subnetted connections: http:[url]....
I can ping R2 to R5 but not R5 to R2. I have spent about 10 hours going through my network and code to no avail. I think it is the frame relay that's causing the error but not sure.. I just checked and I think R6 and R5 are not getting their OSPF updates by trying show ip route
Here are my configs: http:[url]....
I am researching on the behaviors of routers when MTU is increased beyond the MTU set in the routers. Also, when I use jumbo frames instead of normal MTU, how does it affect the network. So, what I plan to do is
LAN_A -- > blackbox --> WAN --------> WAN --> blackbox --> LAN_B
All the traffic coming from LAN_A will be of size 1500 Bytes or less. The blackbox in the center will add an overhead of 4 bytes, recalculate the CRC and transmit the packet on the WAN side. I wanted to know that:
1- if my LAN router and WAN router, both are set at 1500 MTU, then will WAN router drop the packet if it receives a packet greater than 1500B ?
2- If i keep my LAN side to 1500 MTU and I switch my WAN router to Jumbo frames, how will this configuration affect the complete network ? Will it work or not ?
3- I want to add the overhead on every packet coming in from LAN side, so, what options do I have to achieve this goal ?
PS. All types of traffic can come from LAN side.
Main site have 8 departments and each department have 60 pc's,remaining sites each have 6 departments and in each department have 40 pc's and in the design of WAN connection you use frame relays and that is the 100% growng hosptals and clock speed is 64000 bits/sec and security must don't access the unautheraised users from out side....how can I do this?
View 5 Replies View RelatedI am having real problems trying to build resiliency into a hub and spoke frame relay scenario. I know the hub is a single point of failure. Is there any way to put some resilience into the network? There is 4 attached branch offices.
View 8 Replies View RelatedI need netframe v4.0.30319 !!
View 1 Replies View Relatedwe are configuring a ras on 3925 router with e1 controller. when we connect the e1 controller to pbx we got on pbx a no frame alarm (detailed error is that we have nfas but we do not have cas). what could be the error? do the router need dsp to have a framed e1?
View 1 Replies View RelatedProvider T1 handoff with two PVCs to their MPLS cloud to a 2911.One Internet PVC and one for the MPLS including a SIP trunk .
Is there a way to use QOS to have the router prioritize one PVC over the other.Always service the MPLS/SIP PVC over the Internet ONLY PVC?The MPLS/SIP PVC will have QOS for voice but needs to be prioritize.Other option will be to police down the Internet PVC to a value which will leave the required total Kb for the voice priority KB.(FR PIPQ works if the PVC is for voice only.)
working through a lab and can't seem to configure frame relay on subints. I assume it's not supported but this seems basic; am I doing something wrong?
View 4 Replies View RelatedI have been trying to make rip work on this frame relay with multipoint configuration (hub and spoke) and I also configured a loopback interface on each of the routers and configured rip with the loopback address. I observed that the routers (cisco 3600 series) are not sending or receiving any RIP updates through their serial interfaces but are sending through loopback interfaces i configured (debug ip rip).I can ping all routers but cant ping their loopback interfaces because RIP updates are not sent or received by them.
R1#debug ip rip
RIP protocol debugging is on
R1#
*Mar 1 00:09:46.759: RIP: sending v2 update to 224.0.0.9 via Loopback1 (1.1.1.1)
*Mar 1 00:09:46.763: RIP: build update entries - suppressing null update
[code]....
I started studying yesterday for CCNP Route and I'm already stuck. Stupid Frame relay. Basic topology attached, 1 Hub, 2 spokes. I have EIGRP working correctly and each spoke can see all routes correctly. The Hub is on a Multipoint interface with split horizon turned off.
View 15 Replies View RelatedI've a home lab which consists of three 2610xm routers and I have configured two routers back to back with FR subinterfaces. The commands are used are;
R1
frame relay switching
int s0/0
encap FR
no sh
clock rate 64000
frame-relay intf-type dce
[code].....
Everything works great with this config and I know how to configure without lmi too. My question is more for the CCNA exam and fill the gaps in so to speak. The question is when you configure FR with static mappings and inverse arp do you need actual frame relay switches on the other side of the link or can I configure on my home labs routers. I know I am gonna try and configure this as well, but can I configure multipoint on my third router with a different physical interface. Like R1 with s0/0 to R2 s0/0 and R1 s0/1 to R3 s0/0 with subinterfaces.
I noticed that many times the adaptor is tranmitting after other device transmitted CTS. this is a violation of the 802.11 spec
View 1 Replies View RelatedI 'm trying to set up a home lab with a couple of 28XX and 2651XM series routers.I would like to simulate a frame-relay connection between HQ, Branch1 and Branch2 . All of them are conneced to a PSTN switch (2811 router) via T1 cross over cables. The connectivity is like this. [code] I have configured all the routers and FR switch with necessary configuration. However the link between HQ and Branch1 is not coming up. On both the routers I could see the line protocol is down.I have pasted the configuration below.[code]
View 4 Replies View RelatedAs U know cisco feature for frame-relay is creating mfr link and binding them to physical interfaces I did so but my MFR links doesn't get up?
PS. router is ASR1004
frame-relay switching
interface MFR0 description Virtual FR ---> Serial0/0/0 no ip address encapsulation frame-relay IETF frame-relay lmi-type ansi frame-relay intf-type dce frame-relay route 908 interface Serial0/0/0 908!interface MFR1 description Virtual FR ---> Serial0/2/4:0 no ip address encapsulation frame-relay IETF frame-relay lmi-type ansi frame-relay intf-type dce frame-relay route 900 interface Serial0/2/4:0 900
interface Serial0/0/0 (Smart serial interface) description Serial ---> E1 no ip address encapsulation frame-relay MFR1
interface Serial0/2/4:0 (E1 serial interface) description Link ---> S no ip address encapsulation frame-relay MFR0
I am installing an ASA 5520 and I have a problem on accepring the incoming traffic from an external office connected via Frame Relay.
On my OUTSIDE interface I have both the internet traffic and the external office traffic incoming. What comes from the external office is visible as 10.1.0.0/16.
I have to allow this traffic to enter the internal network, without any control. I would also keep the original IP address.
I have configured the Firewall but I don't know how to setup the NAT.
I'm looking to test fram relay connections in a lab environment i'm building at home. I have a couple of 2610 routers that are barebones and am looking to get some serial modules. Are (2) WIC-2T's all I would need to create those test connections? Also on a side note are the any modules for the 2610 that have fast ethernet connections. I would like to have that so I can create a router on a stick model off of the 2600's.
View 1 Replies View RelatedIOS 15.1(4)M1.
I am trying to setup my new 2901 running 15.1(4)M1 for frame realy via a VWIC3-1MFT-T1/E1 card. Now I have set up plenty of frame relay connections via older serial cards, but I just cannot find any documentation on how to do this on one of the new VWIC3-1MFT-T1/E1s. None of the commands I am used to seem to even exist. None of the
encapsulation frame-relay ietf
frame-relay interface-dlci 16 ietf
seems to be there. How to configure the card in IOS 15?
We have frame relay T1 circuit at one of our remote site. Which is connected to our core frame relay router which have DS3 circuit.Now we bought second T1 line at remote site and now I have to configure Bounded T1 with Cisco 1921 router.good config example or document on how to configure frame relay bounded T1 ?
View 1 Replies View RelatedI'm reading this definition in the cisco T-shoot student guide:
"Align-Err: this is the number of frames with alignment errors, which are frames that do not end with an even number of octets and have a bad cyclic redundancy check"
I don't understand what "frames that do not end with an even number of octets" actually means. Did they mean even number of bits? or does a frame's lenght need to be an even number for it to be considered valid?
I've to configure 2620XM router as a frame replay switch. I need 8 interfaces on it. which module should I use?
I'll have other 7 routers connect to it using DB60 cross over cable. 6 of those routers will have WIC-2T card while 1 router will have NM-4A/S card.
I've had a read through the docs for the 3750 series switches, but nothing that definately says that jumbo frame routing will work on a SVI.One part specifically I'd like clarification on is:The default maximum transmission unit (MTU) size for frames received and sent on all interfaces on the switch or switch stack is 1500 bytes. You can change the MTU size to support switched jumbo frames on all Gigabit Ethernet and 10-Gigabit Ethernet interfaces and to support routed frames on all routed ports. It says supported routed frames on all routed ports, but this in the past has meant physical ports, and not Virtual ones.
View 2 Replies View RelatedI have a 3845 running 12.4.13a which I want to upgrade to 12.4.24.After upgrade one of the interface that is configured for frame relay doesn't work anymore.In fact is the "service-module t1 timeslots" commands that can not be executed and the router throws that error.I tested this behaviour on two 3845s and the result is the same.Is this a bug or is an workaround for it?
View 3 Replies View RelatedI have a pair of N7K's in vPC topology with some FEXs attached. I am looking into enabling Jumbo frame on the N7K as well as the FEX. I understand Jumbo frame is enabled globally by default.
My question is I have some interfaces in a port-channel that I need jumbo frame enabled. Do I enable it at the port-channel interface or at the physical interface ? and is the change disruptive to the network ? I am running NX-OS 6.0.2.
Transitioning from 3825 to 3945 (OS is 15.0(1r)M13 c3900-universalk9-mz.SPA.151-4.m4). Turning on FDL on the 3825 was easy but the same command on the 3945 doesn't work.
View 3 Replies View Relatedwe plan to implement the SMB Pro AP541 for a guest access solution.is there a lobby ambassador like on the big wireless lan controller?is it possible to sign a guest a time frame - e.g. guest user has only 60 min access to the internetis it possible to enter a lifetime for the guest user - e.g. guest user can only login until 10.10.2010
View 2 Replies View RelatedIs there a way to configure a switch (3550, 3560,3750) to disable a switch port if it has not been used for a specified time period such as weeks or months. Say you want the switch to disable switch ports that have been "abandoned".
View 8 Replies View Related