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17

Yes, from the packet switching point-of-view, VXLAN is just a matter of sticking some encapsulation on top of an L2 frame: something that other protocols do as well. The real difference it makes is at the control and management layer. VXLAN evolved as a Data Center technology, so the ability to span a WAN is just an additional advantage, not the thing that ...


12

Yes, encapsulation hide the details of what is encapsulated and doesn't really care about the payload nature. VxLAN is a sensible example of this, with layer2 (VLAN) being encapsulated in layer 4 (UDP).


9

Consider a package delivery service, like UPS or DHL. They don't care what's inside the box - they just make sure it gets to its destination. Similarly, the protocol doesn't care what the payload is. It doesn't have to be a higher layer. The idea of a layered protocol model is that the "payload" of a layer can be anything. @JFL gave one example. ...


8

Originally, WANs were mostly defined by specific layer 1/2 protocols (Frame Relay, HDLC, SONET, etc) that they used, but Ethernet has taken over, and the others are rapidly fading into history. The term "WAN" now generally describes a network that covers some larger geographical area than a LAN. Sounds vague? It is. Some WANs, like the Internet are public,...


7

As you've already stated, VXLAN is L2 tunneling over IP. It's a solution to use any L3 network for creating a L2 segment. While this is also possible with other protcols, VXLAN doesn't require additional infrastructure or special transport (given IP is available) and it can also use a single tunnel for up to 16 million subtunnels - with a large ...


6

The tunnel is a point-to-point interface, all packets sent over the tunnel are received and processed by the remote device. When the remote device realizes the packet is destined for a subnet-local address it sends it back across the tunnel to your Microtik. You are hitting a the ping-pong vulnerability in IPv6.


6

I've also read that it's possible to make it appear as a flat network i.e. everything on the same LAN. This is the piece i am missing, can someone help me to understand how this is possible? Some tunneling technologies provide Ethernet over IP services. For instance, research about these topics: L2TPv3 EoMPLS VXLAN EtherIP (RFC3378) Ethernet over GRE Cisco ...


5

Serv, Your tunnel source and destination addresses are wrong. They should be 209.165.122.2 and 64.103.211.2 on RA and the opposite on RB. There are many different ways to explain this, but essentially, the route to the tunnel endpoint cannot be through the tunnel. In your case, in order to send a packet (from RA) to 192.168.1.2, RA has to encapsulate it ...


5

Some vendors support IEEE 802.1ae/MACsec for encryption layer two between the access switch and its endpoints. I'm afraid I can't be any more help as I have no experience with it (and frankly it sounds like a nightmare to administer).


5

Cisco IOS/NX-OS/etc. software does not configure the bandwidth for a virtual tunnel interface based on the physical interface to which it is assigned; instead, it applies a default "bandwidth" statement to the interface that depends on model of hardware and the version of software it is running (on many devices the default "BW" for a tunnel is 8kbps!). As ...


5

The DNS is issued by default from your local host, not from the proxy, when using SOCKS (probably because SOCKS4 didn't support other way). Make sure you have checked the checkbox "Remote DNS" in the Proxy configuration of the Firefox:


5

The consensus of the comments is The segments are inside IPv4 The protocol of TCP happens to be 6 and it's not its IP version number As you say, if you're looking for 4s vs 6s for protocol versions, you will find them!


5

Yes, what's important to the router is layer 3 interfaces. You can think of a layer 3 interface as a logical construct, which can be be tied to a VLAN, physical or tunnel interface.


5

So what's the difference between GRE+IPsec and IPsec only? In GRE+IPsec the original IP packet is encapsulated in a GRE tunnel packet. The GRE packet is then encapsulated in the IPSec packet. The most common reason for doing this is to allow broadcast and multicast across the tunnel. Neither is supported by IPSec alone. GRE can also encapsulate non-IP ...


5

Wan links are provided by service providers wan links are point to point link link a physical cable is connected between both end points .consider to be highly secure no other intruder can access this links it's private lieased link Where as vpn tunnel is build between two different organisation on different locations. Data is encrypted and forward towards ...


5

Encapsulation is the normal method of using a lower layer mechanism for moving your data. E.g. HTTP is encapsulated by TCP, TCP is encapsulated by IPv4, IPv4 is encapsulated by an Ethernet frame. Encapsulating backwards or at the same layer - IP in GRE, IP in IPsec, IP in UDP, Ethernet in L2TP, ... is called tunneling. It somewhat ties a knot in your ...


5

Cisco has a nice IPSec Overhead calculator (CCO Login required, unfortunately). https://cway.cisco.com/ipsec-overhead-calculator/ From where we can draw, based on your IPSec settings and a few common optionals thrown in: 8 PPPoE (optional, but widespread) 20 outer IP header 8 NAT-T (optional, widespread, sometimes even default-on) 8 ESP Header (4 SPI ...


4

GRE is just a tunneling protocol - its main reason for existence is toplogy hiding/bypass. Some examples include: Tunneling MPLS across a network that may otherwise not support it - MPLS shims are not IP-based, therefore wrapping them in a GRE tunnel allows two routers to appear adjacent when there could be a number of intermediate IP-only devices. ...


4

You are confusing me with the "default gateway" thing. The source address is the address on the device from which you are pinging, not the gateway for that subnet. Suppose I have two addresses, 10.11.12.13 and 172.16.17.18 on my computer. I want to ping on the respective interfaces (logical or physical). I ping from the source (-S) with each of the ...


4

Yes it is possible, and Everton gave you some features that help you do that, but... ...please don't do it ! I know a single LAN over two (or more) distant sites seems nice for machine migration (it can keep the same IP) or auto-discovering protocols, but by bridging two remote LAN you create a single failure domain. By bridging remote LAN, you will ...


4

Tunneling involves encapsulating the packets to be tunneled inside an outer packet. The tunneled packets are the payload of the encapsulating packets. You will be creating a new IPv4 packet header to encapsulate the IPv6 packets, just as if the IPv6 packets were TCP segments. The new IPv4 packet headers don't really care what is in the payload, other than ...


4

IKE is (in massively simplified terms/practically explained) just a way of establishing an IPSec VPN tunnel, and IPSec VPN tunnels don't inherently support multicast. You can put a GRE tunnel inside of an IPSec VPN tunnel which will support multicast, and other non-IP Layer 3 protocols, like apple talk, IPX, and NHRP, which explains why DMVPN which uses ...


4

You could solve this by running VXLAN on the hypervisor using software like FRR. That would imply that you run a full mesh BGP setup between your hypervisors, or use route reflectors. Then, you can create as many VNI's between your hypervisors which can be used as VPC's between virtual machines. We've done this in a test setup and it seems to work, so we're ...


4

I've read that IPv6 over IPv4 tunnels are a security risk because IPv6 traffic cannot be intercepted by Intrusion Detection Systems and Firewalls. That's completely untrue. Maybe some specific, very old IDS systems and firewalls are unable to detect this, but modern equipment sure can. However, if a network has native IPv6 support it shouldn't be subject ...


4

Off the top of my head, the most common would be: IPSEC (Internet Protocol SECurity) SSL (Secure Sockets Layer) PPTP (Point-to-Point Tunnelling Protocol) L2TPv3 (Layer 2 Tunnelling Protocol) As for which layers they are each working at, it really comes down to what you mean by "working". L2TPv3, PPTP and IPSEC all establish and operate over the top of IP ...


4

Tunnels change the network topology. They let routers A and B be logically adjacent even if they don’t have a physical connection. They also let you run one type of network over another type of network. Example uses: Run IPv6 network over IPv4-only infrastructure. Connect “internal security zone” networks over “external” routers. Logically connect slave ...


4

Let's say that it is a 'new protocol heavily based on L2TPv2'. It shares a lot of the messages, constructs, flows with L2TPv2 but it is not strictly backwards compatible. It does have an L2TP 'compatibility' scheme as indicated in section 4.7 of the RFC, but that comes with limitations. The most significant changes are actually listed directly in the RFC: ...


4

Two main reasons for using labels: It makes the transport layer independent of the customer addressing scheme. Multiple customers can have overlapping addressing. The transport doesn't care Protocol independence. What you've describe works fine for IP, but MPLS can handle non-IP protocols (L2, pseudowires) too.


4

I found the solution to this eventually, with some help. The issue was that on the ASR side, the tunnel was in its default configuration which uses GRE, which the ASA doesn't support. The solution was to change the tunnel mode to ipsec ipv4 like so: interface Tunnel5 tunnel mode ipsec ipv4 With this done, bidirectional traffic was possible over the tunnel.


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