Sybil Attacks: Nodes and Attack Edges

attack edges

The system is constructed with the formalization of honest and malicious users, which are specifically exemplified in Sybil Guard as nodes. The way to recognize potential attackers is by identifying how many identities one user occupies. For example, honest users have only one identity while the attacker has many identities, which the protocol detects.

As Yu and his contributing experts assert, ‘all honest nodes and sybil nodes in the system form a social network’ (Yu et al., 2008), which is precisely demonstrated in the given figure.

Subsequently, if two users are linked without corruptive intent and form an honest relationship, we call that connection an edge. In contrast, any honest user or node that connects with an attacker forms an attack edge. In the process of regulating potential attackers, this graph proves to be effective. Not only does it limit ‘the number of attack edges’ (Yu et al., 2008), it also concludes with the proposition that reliable users don’t need to form any bonds because they already have established friends, whereas, the intention of sybil attackers is to add friends which inevitably dispatches several attack edges. This model allows Sybil Guard to defend social networks against sybil intruders by obstructing and restricting the number of ‘false’ relationships one attacker creates.



Yu, H., Kaminsky, M., Gibbons, P. B., & Flaxman A.D. (2008). SybilGuard: Defending against sybil attacks via social networks. IEEE/ACM Transactions on Networking, 16(3), 576-589.




Sybil Attacks: Sybil Guard or puzzles?


Sybil Guard is a decentralized system that ‘limits the corruptive influence of Sybil attacks’ (Yu et al., 2008) and determines potential attackers by using a graph system. This innovative system will ensure the verification of Sybil attacks by differentiating links in the graph, between Sybil nodes and human established connections known as honest nodes. In the world of social networking, Sybil Guard works efficiently. Subsequently, this mechanism is comprised with characteristics that will maintain security and trust in online social networking sites by identifying honest and malicious activity among users and networks. These characteristics will include the dissemination of attack edges that are vital to interpret malicious behaviour.

Another algorithm that is proposed is the conception of installing ‘computational puzzles to be solved prior to granting new identities’ (Cordeiro, Santos, Mauch, Barcelos, & Gaspary, 2012). Even though this approach will minimize attackers and the stealth of identities, there is a crucial disadvantage to this protocol. By assigning these puzzles that are targeted to confront sybil activity, honest users are coupled with this intractable task. In defense to this slight flaw, experts recommend higher, more complex puzzles to attackers while genuine users will be conformed to easier puzzles. As a result, by establishing these puzzles, the number of sybil attacks is brought to a minimum without ‘compromising the intrinsic characteristics of P2P networks’ (Cordeiro et al., 2012). In contrast to previous undertaken experiments, this mechanism will possess an ‘adaptive’ puzzle mechanism for identity administration and legitimization. Part 3: Nodes & Attack Edges.


Yu, H., Kaminsky, M., Gibbons, P. B., & Flaxman A.D. (2008). SybilGuard: Defending against sybil attacks via social networks. IEEE/ACM Transactions on Networking, 16(3), 576-589.

Cordeiro, W. L. D., Santos, F. R., Mauch, G. H., Barcelos, M. P., & Gaspary, L. P. (2012). Identity management based on adaptive puzzles to protect P2P systems. Computer Networks, 56(11), 2569-2589.

From Line to Life


The object of art is not to reproduce reality, but to create a reality of the same intensity.” – Alberto Giacometti

Drawing and painting: Two things I enjoy. I came across this drawing of footballer Cristiano Ronaldo that I finished not that long ago, which reminded me how much I love art. Whether they be in graphite black and white pencil or water color, I try to give every piece of my work life. No matter the frustration I might go through, the journey is what counts. With everything we do in life, we learn something new that inspires us to always go one step further – every time. Same goes with art. Sometimes what we don’t expect to turn up right, gets a thumbs up!

I have taken several visual arts classes from contemporary art to a interesting drawing class that has helped me work with various mediums in different ways. In the meantime, my passion for languages, especially the French language and its culture is what I decided to continue on with at university. However, I believe art will always be a part of me and I will continue to draw, create, smudge and paint to my hearts’ content no matter what!