A) Ad-Hoc (Peer-To-Peer) Mode; B) Infrastructure Mode - EnGenius EPI-9701 User Manual

EUB9701/9702 and EPI-9701series --IEEE802.11b/g/n Wireless LAN Client Adapter
b) Infrastructure for enterprise LANs.

a) Ad-hoc (peer-to-peer) Mode

This is the simplest network configuration with several computers
equipped with the PC Cards that form a wireless network whenever they
are within range of one another. In ad-hoc mode, each client is peer-to-
peer, would only have access to the resources of the other client and
does not require an access point. This is the easiest and least expensive
way for the SOHO to set up a wireless network. The image below depicts
a network in ad-hoc mode.

b) Infrastructure Mode

The infrastructure mode requires the use of an Access Point (AP). In this
mode, all wireless communication between two computers has to be via
the AP. It doesn't matter if the AP is stand-alone or wired to an Ethernet
network. If used in stand-alone, the AP can extend the range of
independent wireless LANs by acting as a repeater, which effectively
doubles the distance between wireless stations.
depicts a network in infrastructure mode.
Version 1.0
The image below
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