The Impossibility of Exactly-Once Delivery

Exactly-once delivery defined

First of all:

Exactly-once delivery guarantee is the guarantee that a message can be delivered to a recipient once, and only once.

While having a message be delivered only once by a recipient, is the norm, it is impossible to guarantee it.

Proof by contraposition and the two generals problems

The similarity between the two generals problem and exactly-once delivery is quite striking. We again have two parties trying to communicate some intent, with a potential for loss of packages. Where the two generals had to agree on a time to attack, here the two processes have to agree that the second has successfully received the message.

Let’s assume that a protocol exists which guarantees that a recipient receives a message from the sender once and only once. Such a protocol could then solve the two generals problem! Representing the time of the attack as the message, the first general (the sender) would only need to adhere to the protocol for the second general (recipient) to have received the attack time exactly one time. However, since we know that this is not possible, we also know that exactly once is not possible.

Direct proof

In case it’s easier to conceptualize, I’ll try to prove the impossibility of exactly-once using a direct proof. For this, let’s assume:

1. The sender and recipient are operating in the real world, meaning non-zero transport and processing times (and no strict consistency)
2. The sender and recipient do not have access to each other’s internal state. This means that the recipient is not aware of the intent to send a message unless told by the sender
3. Transport of the messages are unreliable
4. The recipient has to do some processing on the message (this means the message cannot simply be dropped or lost)
5. The operation is time-bound: processing has to complete within a non-infinite period of time

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How to Develop On-Demand Pizza Delivery App?

AppClues Infotech is a mobile app development company providing high-end online and offline custom mobile app solutions to startups, small and medium businesses (SMBs) as well as large Fortune Global enterprises, spread across India, USA and UK.

Depending on the features the price of the application varies to develop On-demand Pizza Delivery App it may cost you around-$7000 to $20000.

Features Of AppClues App develpoment

• Request Management
• Look Menu for Food
• Cook Allocation
• Allotting Delivery to Delivery Men
• Conveyance Tracking for Food Order
• Surveys and Feedback for Order Delivered
• Referral Management (Friend)
• Continuous Communication (For Order Confirmation)
• Limited time Offers (Promo Codes)

Over the past years, AppClues Infotech has been able to successfully deliver and deploy many enterprise and consumer mobile apps for its clients.The applications developed by AppClues Infotech under mobility solutions have been spread across various platforms and development.

Our top-notch engineers craft flawless code for the system with the largest number of users in the world.

Why Choose us ?

• Aligned structure
• Domain Expertise
• On time Delivery
• 24/7 Support
• Detailed analysis
• Aesthetic Designs
• Agile Development
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AppClues Infotech Builds software that makes businesses more efficient and customers’ lives easier is what we’re bet at. Products we create are carefully designed with end users in mind and brought to life with elegantly written code.

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Complete Guide To Make A Food Delivery App Like Postmates

Food delivery apps are buzzing. With people getting more occupied and technology freak, there is a commendable rise in the food delivery app. Food is integral to humans. So, whatever be the situation, the food delivery app is always in demand. Tyro players of the food delivery business are always inspired by big names of the industry like Postmates, Ubereats, Grubhub, etc to name a few. They aspire to make a food delivery app and enjoy seamless growth opportunities.

Let’s learn all about Postmate and how to make food delivery apps like Postmates.

An Introduction To Postmates:

• Postmate was founded in 2011 by Bastian Lehman, Sean Plaice, and Sam Street.

• San Francisco is Postmates headquarters.

• Initially, it started as a courier service delivering consumer goods to the customers.

• It was a revolution in urban logistics with a strong logistic team.

• Postmates integrated technology and a non-standard approach to business. That is everyone can work as a courier which resembles the uber model for drivers partnership.

• Postmates later started an on-demand food delivery service.

• Postmates now partners with almost 600,000 restaurants.

• Postmates covers 80% of the US market of food delivery business.

• Postmates has a presence over 100 metropolitan areas in the USA.

Read complete Article here : https://www.suffescom.com/blog/how-to-make-food-delivery-app-like-postmates/

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Food Delivery App Development

https://www.mobiwebtech.com/on-demand-food-delivery-app-development-like-ubereats-zomato/

If you are interested in creating food delivery clone app of Zomato, Swiggy or UberEats, Mobiweb Technologies is the perfect choice for you as we have in-depth expertise in providing customized food delivery apps. Start live chat with our experts to know more about our food delivery app development in detail.

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Awesome Food Delivery Website Development Tips: All You Need to Know

On-demand food delivery is extraordinary. To start with, it liberates our bustling timetables. With the speed of life a great many people have, cooking is simply one more task that requires significant investment we could spend sharpening the abilities we really need to sharpen. Second, for the individuals who simply loath cooking, delivery is a (for the most part) reasonable path around this issue.

These elements make On-demand delivery benefits exceptionally mainstream, putting them on the rundown of moving application thoughts.

As per a report by Technavio, the food delivery market is expected to develop by more than $104 billion somewhere in the range of 2018 and 2023.

What’s more, that report was posted before the worldwide lockdown brought about by COVID-19 and the ensuing flood in prominence of On-demand delivery administrations.

While the worldwide circumstance is by all accounts improving and a few nations are beginning to lift isolated limitations, On-demand delivery has gotten a major push forward and a gigantic advancement among the worldwide people.

Food delivery is presently probably the most ideal alternative in case you’re thinking about what programming to put resources into during the COVID-19 pandemic.

Food Delivery Marketplace: Website or Application?
You ought to pick the platform on which to dispatch your business with care. A versatile application permits greater adaptability, allowing clients to arrange delivery while driving or while at a companion’s place. Our cell phones are with us in any event.

Then again, very little adaptability is required when the world is in lockdown, isn’t that so? We don’t have a clue how long every specific nation will keep isolated measures, and building a food delivery website is quicker than building an application, which means you’ll begin procuring quicker. It’s significantly less expensive, as well. In the current conditions, it appears to be reasonable to make an online food requesting website first.

A web development companies can generally construct a versatile web app when things are back to ordinary and you have a profit from the venture from your website.

Read the full blog here

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Cost to create a food delivery application similar to UberEats?

Food ordering and delivery from the app are becoming our daily habit, especially in urban cities. The need for food delivery has also increased because the restaurant dine-in is not preferred by most individuals in times of Covid-19. So to enjoy delicious food from their favorite restaurant they can just order it from the app and get it delivered at home in under an hour.

Want to serve foodies with a food delivery app?

Hire experienced Food Delivery App Development Agency WebClues Infotech. With past experience in developing similar apps like Foodie, Edge Smart, MyOrde, etc. WebClues Infotech also offers its expert guidance to new start-ups in developing a Unique Food Delivery App.

Want a detailed guide on How to Develop a Food Delivery App like Uber Eats?

Read more about Food Delivery App Development - https://www.webcluesinfotech.com/cost-to-create-a-food-delivery-app-like-ubereats/

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