I like how everyone is stating tier 1 definition from networking course where they don't provide end-user internet. AT&T, Verizon, and Sprint are all tier 1 ISPs and provide end-users internet plans.
To become a tier 1 network, you need to peer with EVERY OTHER TIER 1 NETWORK which are listed
here .
Peering is an interconnection between two networks in which no one pays the other for network traffic. In other words, every party retains the money they take from their customers. So tier 1 doesn't pay any other network for exchange of traffic.
Tier 2 network: A network that peers with some networks (even Tier 1), but still purchases IP transit or pays settlements to reach at least some portion of the Internet.
While
Tier 3 network: A network that solely purchases transit from other networks to participate in the Internet.
Source .
Transit: The network operator pays money (or settlement) to another network for Internet access (or transit).
Notice that in definition of tier 3, they didn't mention that tier 3 has to purchase from tier 1, 2 or 3. Also they didn't mention who tier 3 networks can sell to as they can sell to OTHER NETWORKS as well as home users and businesses.
From these definitions, Ogero is a tier 3 provider as it only purchase transit from other international ISPs and doesn't peer with any network. Also every private ISP in Lebanon is a tier 3 provider as they only purchase transit from Ogero.