Humm, a little off-topic, but then so is a lot of this thread.
I have noticed that some of the regular posters are once again getting short, to the point of being rude. You guys need to remember that this is a public forum which anybody can join and post on. That anybody will include all levels of experience and many of their posts will be irritating. New users will post questions that have already been asked (yes, there is a search bar!) or in the wrong place. The more regular and experienced users need to at worst simply ignore such posts, or at best redirect the OP to the correct place (whilse swearing quietly under their breath!!!) Simply being rude or, even worse, closing a thread does not help the karma of the forums at all. There were 2 threads recently started by lmce3000 on this very subject:
http://forum.linuxmce.org/index.php?topic=7724.0 and
http://forum.linuxmce.org/index.php?topic=7767.msg50185#msg50185So, it saddens me to see posts like this one from Hari:
and this is related to lmce development in which exact manner?
Yes, it perhaps shouldn't be in this forum, but why not gently re-direct the user to the correct forum?
Hari, I have had run-ins with you before on this subject. I have asked questions and had you (I assume it was you as you responded in the thread) simply lock the posting, preventing others from responding. I was accused of not doing my own research, yet in my posts I pointed out that the wiki was giving conflicting messages and that I was seeking clarification.
Please, everyone, can we try to remain friends and avoid sarcastic or abusive comments? It may be that thinks are said in jest, but it is easy to mis-interpret stuff that is written and offence caused that was not intended.
I know everyone here is voluntary and you all give of your time very generously. This is appreciated and as soon as I am up to speed, I will return my experience to the pool.
Moving back to the OP and question...
What I stated in message #2 I stand by. Yes, a gateway is Layer 4+, but the point being that the OSI model (which is NOT the IP model) has a definate split between Layer 3 and Layer 4. They are often referred to as the "lower layers" and "upper layers" respectively. When the archetects of IP (which has become virtually the only protocol out there now) started naming things, they used the term "gateway" incorrectly. I agree that your default gateway MAY have to act as a proper gateway if a WAN is involved, but this is by no means a requirement. In many applications, a router (=default gateway) is between two ethernet segments. It is this that leads to a lot of the confusion around today. I should know, I teach this stuff for a living and it causes endless confusion when in one breath you use the term "gateway" to mean router and in the next to mean a device to convert ISDN to VoIP!!!! In a home network, based on LMCE, you have this very situation. Your core has two NICs. It routes traffic between the public and private networks. Both are ethernet. When you look at your client's network settings, it has the "Default Gateway" set to be the core, which is acting as a router NOT a gateway. To start justifying it by saying things like
The "default gateway" is used in TCP/IP "speak" as abbrevation for "default gateway router".
is to fall into the Micro$oft trap of redefining standards and terminology and then claiming due to sheer weight of numbers and market penetration that your interpretation is the correct and only one.
I'm sorry, but if we are to be correct, and answer the OP's question, we need to draw this distiction. Routers translate between networks (Layer 3) Gateways between protocols (Layer 4+). As Hari correctly states, the OSI definition (NOT the IP one!) is
"A Gateway operates at the Transport Layer and above. Typically translating each source layer protocol into the appropriate destination layer protocol."
Now, let us all sit quietly in the lotus position for a few minutes, clear our minds and think calming and happy thoughts.....