Problem CosmWasm IBC + permisionless smart contract chains present new usecases and possibilities but also new attack vectors. 2 issues noted CosmWasm contracts can infinite loop over IBC, gets ACK for a previous send packet and then dispatches another msg from that ACK Out of gas issues that can fail processes which leaves pending msgs Not clear if relayer software currently accounts for these issues and if safeguards should be built in at the relayer layer, the IBC layer and/or the smart contract layer.

The Problem After a chain halts and has to be rebooted from a new genesis file the issue arises that the new nodes no longer have state from pre-halt. When updating an on-chain IBC light client after the chain resumes block production, a MsgUpdateClient needs to be sent with a consensus state from pre-halt and so essentially a node with the old state is needed for block heights <= the height in which the network resumes block production at. The Solution To get around this issue we need to hardcode an endpoint for a node that has the chains state pre-halt, which a relayer will use only when block heights from pre-halt are being referenced. This PR in the relayer demonstrates how we achieve this: https://github.com/cosmos/relayer/pull/876 Essentially we just tell the relayer to use this old node whenever block heights from pre-halt are needed to query a consensus state. If you have a binary built from the linked PR then all you would need to do is configure the relayer with all the relevant chains and paths and then send a MsgUpdateClient to both of the path ends.

High Level Scope The ClientState.CheckHeaderAndUpdateState() method has a lot going on but there are really a few core things happening here. Check if the provided Header is invalid Client or header provided are not parseable Header is invalid Header height is less than or equal to the trusted header height Header revision is not equal to trusted header revision Header validator set commit verification fails

The Issue The juno-1 mainnet halted on block 2578108. ... Solution As per the IBC documentation here In the case that a highly valued light client is frozen, expired, or rendered non-updateable, a governance proposal may be submitted to

We will configure the relayer to work with the Axelar and Juno testnets in this example but all the steps would be the same for whichever networks you choose to relay on. This example assumes you have the relayer binary built already. Setup Config Initialize the relayers config. rly config init Add chain config files for both the src and dst.

Changes The new relayer has several improvements with big goals in mind Eliminating Bech32 issues by relying on lens as a dependancy as a means for avoiding the global singleton in the Cosmos SDK Paving the way for other ecosytems to integrate with IBC and find support in the go-relayer, this is achieved through the concept of a Provider interface which is a feature rich API that can be implemented Creating a consistent cli experience for users which is both easy to use and feature rich Better tx flow where you submit a tx and wait until it is included in a block Adding Additional Provider implementations For those interested in finding support in the go-relayer a few steps must be adhered to.

Buying tapes/DVDs of recorded television broadcasts online from sites like eBay is becoming harder and harder as time goes by. These days there is an ever growing list of people reselling content they find on sites like MySpleen, Internet Archive, VHSTapes.org, Nostalgic, etc. This makes it almost unbearable for those of us still looking for original content that has not been shared with the community. The only way we are going to beat these bastards is by working together as a team and restoring a higher sense of community amongst tape collectors. I've started to see some truly clever tactics these days. Sellers like ramblingtrader are cutting episodes out of different recordings available on MySpleen and then splicing them together with the commercial breaks to make their listings appear like original content unless you REALLY look through all the available tapes with similar content (i.e. if you see a tape for sale containing Toon Disney shows, you must look at all available Toon Disney recordings and ensure the tape for sale isn't spliced together with a mix of content from all the already available recordings). It's clear that this is becoming out of hand and it's too much for a single person to manage on their own. I believe that by working together and shedding light on these resellers we can really disincentive the act of reselling tapes, or at the very least make it easier for MS users to tell them apart from the people actually selling tapes on eBay. Thread Rules When posting the name of someone you know to sell dubs/copies of content from MS or any other online community, be sure you are posting their actual username and not just a link to their eBay account or an item listing. Links are not very reliable on the internet and many die soon after being shared on forums pages like this. By posting the name here instead of a link you ensure that people in the future have reliable access to this information. When posting the name of someone you know to sell dubs/copies be sure to double check the list to ensure we aren't double posting.