Author: Biteye core contributor Crush
Editor: Biteye Core Contributor Crush Community: @BiteyeCN
Now that the on-chain ecology is so rich, cross-chain bridges have become an indispensable part of the entire ecology. Although news of cross-chain bridge thefts appear frequently, it still provides convenience for users to transfer assets.
With the development of Ethereum's second-layer networks such as Arbitrum and Optimism, some cross-chain bridges focusing on asset transfer between L2 have gradually emerged. Today’s article will introduce you to two very practical cross-chain bridges-Orbiter and Layerswap.
By introducing the principles, operations and some details of these two cross-chain bridges, we can help everyone understand the current status of the second-layer cross-chain bridges and make it easier for them to make the best choice when crossing chains.
01. Why choose Layerswap and Orbiter
Some readers may wonder, there are so many cross-chain bridges on the market, why don’t we mention others, but only pick out these two for introduction? There is a deeper meaning in this, let me explain it in detail.
Official endorsement
First of all, what is the most important thing about a cross-chain bridge? I said security, and no one should disagree! As an asset transfer tool, just like the escorts of goods in ancient times, security is naturally the top priority. In addition to the various thefts of cross-chain bridges I mentioned at the beginning, an unsafe cross-chain bridge will definitely not be used by users even if it pays for the handling fee.
Opening the official websites of zkSync and Starknet, you can clearly see that these two cross-chain bridges are at the top of the official recommendations. With official endorsement, their credibility naturally increases.
(zkSync Lite official recommendation)
(Starknet official recommendation, https://www.starknet.io/en/ecosystem/bridges-and-onramps)
Airdrop Expectations
As a Web3 user, airdrops are a reward that you cannot miss. Among all airdrops, public chain airdrops are usually the most generous and have the widest coverage. The two most anticipated public chain airdrops at the moment should be zkSync and Starknet.
If you want to get the airdrops of these two chains, you must experience their ecosystems. Orbiter and Layerswap have both laid out these two chains early on, and users can easily transfer assets from other chains to zkSync and Starknet.
In addition, these two projects themselves have never conducted airdrops. If users give priority to using them when experiencing the new chain, they can achieve the effect of killing two birds with one stone and obtain two airdrops of the public chain and the cross-chain bridge.
02. Principle and operation
Principle Introduction
1.Orbiter
As users, we don’t need to fully understand every step of the operation of the cross-chain bridge, but we can still learn the basic principles. After all, it involves the security of our own funds. After understanding it, we will feel more at ease using it.
When Orbiter conducts cross-chain transactions, there are two roles: Sender and Maker. Before providing services to cross-chain initiators, market makers need to deposit excess margin in Orbiter's market maker margin contract and deposit Liquidity funds in the Maker address to ensure that the Sender's funds can cross the chain normally.
(Note: The Maker address here is an EOA address configured by the Maker itself, which can only be controlled by the Maker itself.)
Suppose we now have a fund of 0.1ETH to be transferred from Arbitrum to zkSync. The normal process is that the Sender sends the funds to the Maker on Arbitrum. The Maker needs to know the target network, that is, which chain the funds will cross to, as well as the amount and type of funds.
After confirmation, Maker will send an asset to your wallet on the target network, which is zkSync, and the entire cross-chain process is completed.
The target network is distinguished using something called an Identification Code, which is added to the last four digits of the transfer amount when crossing chains. By checking the identification code, Maker can confirm the target chain.
(Identifier) 
(identification code of different chains)
Maker is equivalent to a transfer station for funds in the entire cross-chain process. In this process, if Maker fails to successfully send Sender's assets, Sender can initiate an arbitration request to the market maker margin contract (MDC) based on the identification code and other information provided in the transaction approval interface to obtain excess compensation.
2.Layerswap
Layerswap does not disclose much about the technical principles in its user manual, but judging from its early cross-chain style, Layerswap is still different from Orbiter mentioned above.
In the early days of Layerswap, the second-layer network was not yet mature. Many users who wanted to experience the second-layer such as Arbitrum and Optimism could only withdraw funds from the exchange to the ETH mainnet, and then use the official cross-chain bridge from the mainnet to cross-chain the assets to the second-layer.
At that time, Layerswap launched a tool called Bransfer and registered its own accounts in major exchanges. If users need to cross-chain ETH to the second-layer network, they only need to transfer assets to Layerswap's exchange account, and then they will send a sum of funds to your target address on the second-layer network.
Since there is no transaction fee for internal transfers within the exchange, all you need to pay is the fee for the second-layer transfer, plus some fees charged by Layerswap itself, which can be said to be very cheap.
How to confirm internal transfers? Bransfer is used here. Users need to apply for a read-only API on the exchange. Once Layerswap gets your API, it can read your transfer data.
（Bransfer connection interface）
With the development of the second layer, most exchanges already support deposits and withdrawals of Arbitrum and Optimism, and even zkSync and Starknet, which have not yet issued coins, are gradually being supported.
Once the exchange supports these second layers, Layerswap seems to have lost its advantage. Therefore, in the latest v2 version, Layerswap migrated Bransfer and made it a built-in function, and users no longer need to register Bransfer.
In addition, due to the merger of the two, their transaction history has also been unified, and users can view it directly on Layerswap.
Judging from Layerswap’s history and the current cross-chain funding restrictions, we can guess that it is likely to use its own funds to help users cross chains and earn money from transaction fees.
Actual operation
1. Orbiter
https://orbiter.finance
Here I will demonstrate the cross-chain from Arbitrum to zkSync Era. First, we open the Orbiter website and use the V2 version directly, which supports more cross-chain tokens.
(Orbiter cross-chain interface)
As shown in the picture, the interface is very simple. Just select the corresponding chain, token, and fill in the quantity. The bottom will show how much GAS fee and time you have saved. If you want to see the actual cost, put the mouse pointer on the question mark to show the cost of the official cross-chain bridge and the cost of using Orbiter.
(Cross-chain fees)
If you want to check your cross-chain history, you can check it in the History in the upper right corner. In addition to the cross-chain function, orbiter also launched an L2 data dashboard. Click L2 Data in the upper left corner to see the overall transaction data of the second layer and the individual data of each project.
（L2 Data）
2. Layerswap
https://layerswap.io/app
Open Layerswap’s official website. Since it supports direct cross-chain exchanges, here we try to cross-chain from OKX ETH to zkSync Era.
(Layerswap cross-chain interface)
After selecting OKX and zkSync Era, enter the amount to be transferred across chains. The token type cannot be changed here. Only ETH can be selected, and the maximum limit is 1 ETH.
There is a customer service button in the upper right corner. If any problems arise during the cross-chain process, you can contact them directly. The historical records can also be seen in "Transfer".
The number of tokens you will receive will be shown at the bottom, and here it shows that I will receive 0.99802 ETH, including 0.001198 ETH Layerswap Fee and 0.01 Exchange Fee.
For the receiving address, you can fill in the same address as the sending address, or you can customize another address, which is more convenient.
After clicking "Swap Now", you will enter the transfer interface. You need to withdraw 1 ETH from OKX and send it to the payment address it provides you. The public chain to send here can be selected. The default is Arbitrum to save handling fees.
（Transfer page）
Once you have completed the withdrawal operation from the exchange to this address, this interface will automatically detect the arrival of funds and then transfer the funds to your zkSync Era address.
03. Detail comparison
Number of public chains supported
(Number of public chains supported)
In terms of the number of public chains supported, Layerswap has two more than Obiter, namely Solana and Avalanche, and separately supports cross-chain exchange withdrawals.
But more does not mean better. After the collapse of FTX, Solana is no longer as active as before. The entire Avalanche ecosystem does not seem to have any particularly eye-catching projects, and the overall activity is also average. Therefore, the lack of support for these two chains is not a big problem for Orbiter.
Cross-chain speed
In terms of cross-chain speed, we cross from any chain to zkSync Era.
The time for Orbiter is generally around 30 seconds, and the main network is slightly slower, which may take 45 seconds. If the main network is slow, it may take even longer. The fastest is the BSC network, which only takes 15 seconds to cross the chain to zkSync Era.
Layerswap cross-chain speeds are generally slower, generally around 2 minutes. Among them, polygon cross-chain to zkSync Era is the slowest, taking more than 1 hour.
(Polygon cross-chain reminder)
Therefore, in terms of cross-chain speed, Orbiter still outperforms Layerswap.
Cross-chain fees
Most of the cross-chain fees between the second layers of Orbiter are between 2U and 4U, which are usually fixed. A few cross-chain fees increase with the increase of the cross-chain amount, such as the cross-chain of ETH from zkSync Era back to Arbitrum.
(Transaction fee for cross-chain 0.01E)
When the cross-chain amount is 0.01 ETH, the fee is 2.47 U.
(Transaction fee for cross-chain 1E)
When we tried to increase the cross-chain amount to 1ETH, the cross-chain fee immediately rose to 4.43U.
The cost of crossing from the second layer to the main network is high, starting at 14U. The larger the cross-chain amount, the higher the fee, up to 20U. There is no higher fee because Orbiter's Maker has restricted the funds that can cross to the main network, with a maximum of only 10E.
(Transaction fee for cross-chain to mainnet)
The cross-chain fees between Layerswap layers are basically around 0.0016E, or 3U. Regardless of how the cross-chain funds change, the handling fee remains relatively stable.
(Transaction fee for cross-chain transactions between the second layers)
When we tried to transfer funds from the second layer to the Ethereum mainnet, the handling fee was actually cheaper than transferring between the two layers. From the overall experience, we can find that the cross-chain fee of Layerswap is relatively stable, just like the withdrawal fee of the exchange.
(Cross-chain fees from Layer 2 to the mainnet)
In comparison, Layerswap seems to be slightly better in terms of cross-chain fees.
In addition to viewing cross-chain fees directly on the cross-chain bridge, you can also use Chaineye to query cross-chain fees.
https://chaineye.tools/bridge
After opening the tool, enter the relevant information of the cross-chain, and you can query the fees of each cross-chain bridge with one click.
(Chianeye queries cross-chain fees)
By default, the tool will rank the chains from low to high based on the transaction fee. You can change the "cheapest" in the upper right corner to "fastest". This will display the fastest chain.
(Sort by cross-chain fees from low to high)
(Sort by speed from fastest to slowest)
safety
Based on the principles mentioned above, Orbiter uses a whitelist mechanism to allow multiple funded market makers to provide users with cross-chain liquidity on each chain. At the same time, it avoids the risk of market makers not taking action after receiving funds through a margin and arbitration mechanism to ensure the safety of users' funds.
Compared with Layerswap's single entity providing liquidity, the former seems to have more comprehensive considerations in ensuring the security of user funds.
04. Conclusion
Generally speaking, based on the above discussion, we can use the following strategies to complete daily cross-chain operations:
1. When the cross-chain funds are not large, Layerswap is preferred, which has lower fees but a slightly slower speed;
2. When the cross-chain funds are large, Orbiter is preferred. Orbiter's liquidity is obviously more sufficient and can meet the cross-chain needs of larger funds, while Layerswap has a limit of 1ETH;
3. When you need to cross the chain from the second layer to the main network, Layerswap is preferred. The cost from the second layer to the main network is still the cheapest;
4. If the funds are in the exchange and you want to directly cross the chain to the target chain, Layerswap is the first choice, after all, it is the only one that supports exchanges;
5. Users who care about time and security but don’t care about transaction fees can give priority to Orbiter.
Source: L2 cross-chain bridge war: Orbiter VS Layerswap (qq.com)