This reasonably technical web page explains all the main points about 802.1X networking.
What might be blocking the connection is that your MacBook can not move authentication particulars to your college’s community authentication server. In different phrases, units you need to hook up with your MacBook’s WiFi can not authenticate towards the college’s community. That is truly an excellent factor for safety causes.
Not understanding the precise networking settings your college gives makes a fuller rationalization troublesome.
The textual content under is copied verbatim from @grawity’s hyperlink within the feedback under. I need to thank @grawity for giving the right reply for all of us.
There are two explanations [as to why the original answer isn’t true] that interleave a bit; both of them may be sufficient by itself and make the opposite moot, however each are essential for basic understanding.
One preliminary level to remember is that there is not any single entity that could possibly be referred to as “the community” that you’d authenticate to; a community solely exists so far as it is made out of distinct units that hopefully are configured the identical, however in the end deal with issues like authentication independently from one another.
Individually from that, there are at the very least two distinct networks – the Ethernet/Wi-Fi (“native community” or “bodily community”) layer and the IP (“internetwork”) layer – that every have their very own logic and gear. Whereas I am intentionally avoiding the retrofitted OSI-model terminology, its basic concept remains to be related: the gear that includes an Ethernet/Wi-Fi community principally does not care about what sort of IP or non-IP information it is carrying.
802.1X originates as an Ethernet know-how, meant for limiting entry to particular person ports of an Ethernet swap. The way in which it really works there may be that you simply join your laptop to an Ethernet port and it’s a must to authenticate to that individual swap earlier than it “opens” the port for sending/receiving Ethernet-level packets.
Though the auth messages are [usually] forwarded to a central level for analysis, they nonetheless end in a really localized standing change; your swap marks your port as ‘open’ whereas the remainder of the community (past that particular swap) is unaware of any authentication having been achieved.
As soon as the port is open, it’s open for transmission of any information – because the authentication is dealt with by Ethernet gear, it has no restrictions on what sort of IP (or non-IP) packets might go over it.
The place 802.1X is used with Wi-Fi (as WPA-Enterprise), it occupies the identical place as WPA-Private/PSK (i.e. not as an extra safety layer however strictly as a substitute; the person Wi-Fi entry factors (APs) deal with each varieties the identical approach); and each sorts of WPA more-or-less mimic the Ethernet habits, in that your laptop nonetheless authenticates to that individual access-point earlier than the AP “opens” the port for sending/receiving Ethernet-level packets. (Certainly the WPA messages are precisely Ethernet 802.1X messages, and plenty of working techniques use the identical software program for WPA as they do for Ethernet 802.1X.)
After all, there is not any such factor as bodily ports in a wi-fi community, however Wi-Fi nonetheless has an idea of ‘affiliation’ that roughly represents an Ethernet-like connection, tied to your machine’s MAC deal with.
A big college’s Wi-Fi community will encompass many Wi-Fi entry factors, however the machine at all times associates to a selected one at any given time, and solely that single entry level will relay your information to/from the community, thus it acts more-or-less like your ‘community port’ for the length. (Once you transfer round, the machine will roam – affiliate to a unique entry level, which often entails a complete new 802.1X authentication to the brand new AP, whereas the earlier AP forgets about you.)
As soon as your machine associates to the entry level, its “port” is “closed” till the WPA authentication is completed; and as soon as authenticated, the AP will start tp relay something from the machine’s MAC deal with. The mechanism is similar for each WPA-Private and WPA-Enterprise – though the previous is evaluated by the AP itself whereas the latter is [usually] forwarded to a central server for analysis, the outcome remains to be localized throughout the Wi-Fi AP.
Thus, units don’t authenticate to the community as a complete – they authenticate to the bodily machine they hook up with; and when “hotspot” or “web sharing” is in use, ‘borrowing’ units solely must authenticate to the ‘sharing’ machine which then relays information on their behalf. They do not must additional authenticate to the unique Wi-Fi entry level as a result of they haven’t any bodily connection to it.
A lot of the earlier rationalization is definitely moot, because the second level is that “hotspot” or “web sharing” mode often is inbuilt such a approach that it turns the machine into a completely functioning ‘wi-fi router’.
That’s, a smartphone in “hotspot” mode (or a laptop computer in “web sharing” enabled) will even have its personal IP subnet for its purchasers; it is going to challenge IP addresses by way of DHCP; and most significantly, it is going to carry out IP-level NAT to “cover” its purchasers’ IP addresses from the broader community. So far as the community is worried, all the ‘borrowing’ units are invisible, neither at Ethernet/Wi-Fi layer (resulting from routing), nor at IP layer (resulting from NAT) – it is as if the one ‘sharing’ machine originates each single packet.
(There’s a option to detect, at IP stage, that one thing is behind the ‘sharing’ machine – it is how some networks are capable of forbid hotspot/tethering solely – but it surely on no account entails 802.1X or WPA authentication, and it can not actually discern what number of units or what sort of units are behind.)
Thus, even when there have been some sort of authentication at the next stage above the bodily Ethernet or Wi-Fi connection – such because the “captive portal” browser-based login screens that public networks use – because of NAT, the ‘sharing’ machine would nonetheless be capable of piggyback by itself authentication to relay packets from the ‘borrowing’ units in a approach that the community remained unaware of them.
