It looks like in the context of peeragogy, there's a specific but also relatively vague notion of what a peer is.
There are many types of groups. A group is a generic concept for defining arbitrary boundaries of who is in and out, and how those inside relate to each other, and how the inside relates to the outside. These boundaries don't need to be fixed/strict, but it would become pointless to speak about a "group" if it's identical to the implicit group that already includes everybody. Some groups are internally structured hierarchically in terms of power/control, others have carefully designed procedures in place of how to exercise power (the control is in the procedure), and there's a whole bunch of other metrics/dynamics apart from power/control that can be set up differently (money flows, distribution of work, mindshare, sympathy, etc.). "Peer" probably means that there is an outside that doesn't apply peer principles, but the peers inside a peer group are all equal as in sovereign (over their own matters/actions), not as in similar/identical.
Modern peer theory is of course heavily influenced by the nature and architecture of computer networks. However, before that, the "peer review" at universities and in academic journal publishing is already a good example of what the term probably means, as the researcher submits his work for review by his/her "peers" who are supposed to be "equal" researchers in the same field just like him/her. At another time, the researcher having his/her paper reviewed by his/her peers may participate in the review of somebody else's submission, potentially by one of his former reviewers. To establish some equality, the reviewers can be all anonymous, so there's less/no interference for the decision based on sympathy/disregard, position, reputation, personal benefits/favors or similar.
In practice, in a group of self-sovereign, independent peers, some effects are not unlike anarchy (which isn't chaos or the absence/lack of power/control, but the refusal to accept unjust power/control, so in a meritocratic way, what actually happens gets constantly re-negotiated/challenged). However, peer principles aren't identical to anarchy, as the latter political concept mostly addresses the physical space, in which group members are hardly ever "equal" in the sense that they may be independent of each other, as a result of the scarcities that are present in the physical world of time, matter and location.
Digital and computers are different however. Before and besides the Internet, there have been many other networks for transmitting information, be it the telegraph or the telephone, or the networks of banks or airlines, digital and non-digital. In contrast, the kind of computer networks the ARPANET/Internet/LANs belong to have some very interesting features of systemic architecture designed into them, which contributed significantly to their success over all the other network types, and this is too where we get the modern peer concept from.
In the early days of computing, there wasn't any standardization of components and protocols, every machine more or less a separate project in the domain of electronics. Wiring these together and make them talk therefore was naturally a huge challenge. There's a lot of not well known background around J. C. R. Licklider, Robert W. Taylor, Douglas C. Engelbart, and historically, I want to also include Paul Otlet and Vannevar Bush. Practically, BBN Technologies (Bolt Beranek and Newman) was tasked with the implementation, from where we get this great piece of presentation:
in which Robert E. Kahn explains the main systemic tool for managing complexity, to abstract/hide the details away with the help of interfaces. Also, from the Turing test, if the interface of communication are just the bits (electronic signals) that go over a wire in the wall, all the other network users and machines are just as equal peers as oneself, because all they can do and what they look like is, too, just a bunch of bits that come back and are received. If all network participants agree to be equal and use the same digital encoding of information for data transmission, it's pretty difficult to have one party gain power/control over what the other peers can encode, what they can and can't talk about. Furthermore, on the physical and logical level of the transmission over wires, as the architecture is designed to allow communication packets to use different routes, there's no central node that could block a transmission. With strong asymmetric encryption (as implemented in HTTPS), the nodes between sender and receiver don't have the power to read/spy on the data message payload or alter it. All of this doesn't mean that there are special machines involved for special purposes, that network operators wouldn't gain power over other participants by (legitimate) control/power over their own activities combined with their sheer size which starts to make other parties dependent on them, that bad actors can try to ruin the party for everyone with acts of vandalism, that the governments of the world try to have a say and dictate what the technology can and can't do, that it matters a whole lot how your wire in the wall (the "last mile") is set up, and if the user chooses voluntarily to get into many artificial legal and technical dependencies on the level of data lock-in, software functionality or service offerings. Still, it remains important to realize/recognize that in the digital context, cheap electronics and our particular network architecture means that there's no participant in the network that holds some special privileges or authority over what all the other participants may or may not do. Peers each decide for themselves, with whom else they want to engage, and how.
With the network, it's already very apparent that this peerness is deliberately designed into the technical architecture of digital data transmission, and this aspect alone has several conceptual layers of its own. Just consider the OSI reference model - and likewise, it's not too farfetched to assume that there are many more layers to be found higher and lower (for example: what about the electricity that powers the transmission and digital encoding, contractual obligations, social norms/expectations, etc.), for which one might as well ask if the groups that exist on these other levels are based, designed and operating on peer principles as well. Most of the time, they may not, because it's relatively difficult to establish and protect an equal status (not just in theory, but also in effect!) for all of the participants, which is naturally found in non-physical, virtual of information encoding. Nonetheless, from the example of computer networks, some methods can be learned for introducing more peerness to other domains: designing open standards/protocols for interactions allow peers to adopt and change/expand them, and who isn't adhering to these and instead runs his/her own incompatible operation, already self-excluded him-/herself from the peer group by not speaking the shared language. Once using the shared languages (there can be many in parallel), these can be adjusted, but only in ways that don't grant certain participants special power/control over the other group members. Practically, if a party tries to introduce new modifications that would award itself or some other parties a certain advantage, but not some other members of the group, the other participants may simply refuse to accept these changes, and even if the former large group splits off into two that disagree on these changes and use different standards, these are still two separate groups of peers, within which the peer members remain equal amongst each other.
Typical examples for the effects of actual peerness can be found in
The Pirate Bay – Away From Keyboard
One doesn't necessarily agree with the approach of these copyright pragmatists ("pirates"), but because of the truly peer-based network, they're in effect no different in control and power than law enforcement, Hollywood, you or me, which too all count as a single node of one, no matter if there's a multi-billion company or the government of a state behind it or just a kid with a computer, each with just a single vote, each enabled to do the very same kind of actions, without a way to permit one party and restrict the other.
Now, what does this mean for peeragogy? In what way and on what levels do peer principles apply?