As a side benefit, the MAC also covers the key's comment, preventing any possible mischief that might be possible if someone were to swap two keys and interchange the comments. Thus, we provide the convenience of having the public key available in plaintext but we also instantly detect any attempt at a tampering attack, giving a combination of security and convenience which I do not believe is found in any other key format. For this reason, PuTTY's key format contains a MAC (Message Authentication Code), keyed off the passphrase, and covering the public and private halves of the key. Key formats which store the public key in plaintext can be vulnerable to a tampering attack, in which the public half of the key is modified in such a way that signatures made with the doctored key leak information about the private half. pub alongside it, and then be very confused by the resulting SSH authentication process!). pub file for this purpose if it appears alongside the private key file, but this is a source of confusion as often as convenience (I've seen people replace a private key file and leave an out-of-date. PuTTY's format stores the public key in plaintext and only encrypts the private half, which means that it can automatically send the public key to the server and determine whether the server is willing to accept authentications with that key, and it will only ever ask for a passphrase if it really needs to. In particular, this means it has to ask for your passphrase before it can even offer the public key to the server for authentication. OpenSSH's private key format encrypts the entire key file, so that the client has to ask you for your passphrase before it can do anything with the key at all. Public half of key is stored in plaintext.The advantages of the PuTTY key format are: This review will contribute further research improvements and a road map in order to support in developing the PEM water electrolyser as a commercially feasible hydrogen production purpose.They both store an "RSA key pair for version 2 of the SSH protocol" and can be converted interchangeably however, regarding the actual stored format difference:
In this present review, we discussed about the recent developments in the PEM water electrolysis including high performance low cost HER and OER electrocatalysts and their challenges new and old related to electrocatalysts and PEM cell components also addressed. Thus the considerable research has been completed recently in the development of cost effective electrocatalysts for PEM water electrolysis. Nowadays, increased the desire production of green hydrogen has increased the interest on PEM water electrolysis. However, overall water splitting resulting in only 4% of global industrial hydrogen being produced by electrolysis of water, mainly due to the economic issues. Moreover, the produced hydrogen (H 2) and oxygen (O 2) directly used for fuel cell and industrial applications. However, In terms of sustainability and environmental impact, PEM water electrolysis was considered as most promising techniques for high pure efficient hydrogen production from renewable energy sources and emits only oxygen as byproduct without any carbon emissions. Among many hydrogen production methods, eco-friendly and high purity of hydrogen can be obtained by water electrolysis. Hydrogen can be obtained from different sources of raw materials including water. Hydrogen is the most efficient energy carrier.