Exploring architectures and capabilities of foundational LLMs

Or Jacobi
Or Jacobi

Or is a software engineer at Aporia and an avid gaming enthusiast "All I need is a cold brew and the controller in my hand, and I'm good to go."

8 min read Feb 01, 2024

When talking about artificial intelligence, Large Language Models (LLMs) stand as pillars of innovation, reshaping how we interact with and understand the capabilities of machines. Fueled by massive datasets and sophisticated algorithms, these monumental machine-learning structures have taken center stage in natural language processing. 

Let’s analyze the core architectures, particularly emphasizing the widely employed transformer models. We will investigate pre-training techniques that have shaped the evolution of LLMs and discuss the applications where these models excel.

What is an LLM?

A Large Language Model (LLM) is an advanced AI algorithm that uses neural networks with extensive parameters for a variety of natural language processing tasks. Trained on large text datasets, LLMs excel in processing and generating human language, handling tasks such as text generation, translation, and summarization. Their vast scale and complexity make them pivotal in modern natural language processing, driving applications like chatbots, virtual assistants, and content analysis tools.

A survey of large language models shows that LLMs demonstrate proficiency in content generation tasks utilizing transformer models and training on substantial datasets. Often interchangeably termed neural networks (NNs), these computing systems or AI language models draw inspiration from the human brain.

How do LLMs work?

Large Language Models (LLMs) rely on machine learning methodologies to enhance their performance through extensive data learning. Employing deep learning and leveraging vast datasets, LLMs excel in various Natural Language Processing (NLP) tasks. 

The widely recognized transformer architecture, built on the self-attention mechanism, is a foundational structure for many LLMs. From text generation and machine translation to summary creation, image generation from texts, machine coding, and conversational AI, LLMs showcase versatility in tackling diverse language-related challenges.

LLM architecture

As the demand for advanced language processing grows, exploring emerging architectures for LLM applications becomes imperative. The structure of LLM is influenced by several factors, encompassing the model’s intended purpose, computational resources at hand, and the nature of language processing tasks it aims to perform. 

Widely adopted in LLMs like GPT, BERT, and RAG, the transformer architecture plays a crucial role. Additionally, tailored for enterprise applications, other LLM architectures such as Falcon and OPT bring specialized design features to meet distinct use cases.

LLM architecture explained

The overall architecture of LLMs comprises multiple layers, encompassing feedforward layers, embedding layers, and attention layers. These layers collaborate to process embedded text and generate predictions, emphasizing the dynamic interplay between design objectives and computational capabilities.

LLM architecture diagram

Here’s the emerging architecture for LLM applications 

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Here’s another LLM system server architecture: 

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Transformer architecture

The Transformer deep learning architecture is a revolutionary milestone in language processing, particularly in the domain of Large Language Models (LLMs). A transformer model, introduced in 2017 by Ashish Vaswani and teams from Google Brain and the University of Toronto, is a neural network that captures context and meaning by analyzing relationships within sequential data, such as the words in a sentence. 

Transformer models discern nuanced connections among even distant elements in a sequence using evolving mathematical techniques known as attention or self-attention. This innovative architecture has found implementation in prominent deep learning frameworks like TensorFlow and Hugging Face‘s Transformers library, solidifying its impact on the landscape of natural language processing.

Transformer models

Various transformer models, such as GPT, BERT, BART, and T5, encompass the language processing. The transformer architecture, renowned as the foremost Large Language Model (LLM) framework, illustrates its versatility and prominence in advancing the capabilities of language-centric AI systems.

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Transformer Explained

The core idea behind how transformer models work can be broken down into several key steps:

  • Input Embeddings: The initial step in transformer models involves converting the input sentence into numerical embeddings, representing the semantic meaning of tokens within the sequence. These embeddings can either be learned during training or obtained from pre-existing word embeddings for word sequences.
  • Positional Encoding: To understand the sequential order of words, the input undergoes positional encoding. This process encodes the input based on its position in the sequence, enabling the model to comprehend the contextual relationships between words.
  • Self-Attention: Transformer models employ a crucial mechanism known as self-attention, allowing the model to weigh the significance of individual words in the input sequence. This attention mechanism enables the model to focus on relevant words and capture intricate relationships between them.
  • Feed-Forward Neural Networks: Following the self-attention phase, the model utilizes feed-forward neural networks to enhance the information contained in the representations. This step contributes further insights to the model’s understanding of the input sequence.
  • Output Layer: The final output is generated based on the transformed representations obtained through the preceding steps, reflecting the model’s interpretation of the input sentence.

GPT Architecture

GPT is an autoregressive language model utilizing deep learning to produce text with a human-like quality. 

Let’s discuss GPT meaning and GPT model architecture. 

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GPT Meaning

GPT, or Generative Pre-trained Transformer, represents a category of Large Language Models (LLMs) proficient in generating human-like text, offering capabilities in content creation and personalized recommendations.

GPT model architecture

The architecture of the GPT model is rooted in the transformer architecture, undergoing training with a substantial text corpus. With three linear projections applied to sequence embeddings, the model efficiently processes 1024 tokens. 

Each token seamlessly traverses all decoder blocks along its path, showcasing the effectiveness of GPT’s Transformer-based architecture in handling natural language processing tasks.

ChatGPT model

While sharing the foundational architecture of the GPT family, ChatGPT is fine-tuned specifically for engaging in natural language conversations. It excels in generating contextually relevant and coherent responses, making it particularly adept at mimicking human-like interactions. 

This specialized model caters to a wide array of applications, ranging from customer support bots to interactive virtual assistants.

What is ChatGPT?

ChatGPT is a type of LLM that is specifically designed for chatbots or conversational applications. Incorporating conversational context into its training data equips ChatGPT LLM to produce responses that exhibit linguistic coherence and adapt to the nuances of ongoing dialogues. ChatGPT extends its capabilities to tasks such as text generation, machine translation, summary writing, image generation from texts, machine coding, and chatbots.

ChatGPT Capabilities 

So, if you are wondering what is chatGPT capable of? From answering queries and simulating realistic conversations to creative text generation, ChatGPT’s capabilities encompass a dynamic range of applications. 

Comparing GPT-3 to GPT-4

GPT-3 architecture

Generative Pre-trained Transformer 3, or GPT-3, stands as a remarkable language model crafted by OpenAI. Developed by OpenAI, GPT-3 boasts a staggering 175 billion parameters, making it one of the largest language models to date. The architecture retains the fundamental principles of the GPT series, featuring multiple layers of attention mechanisms and feedforward networks.

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GPT 4 architecture

GPT-4, the latest iteration of OpenAI’s Generative Pre-trained Transformer series, takes strides in three pivotal dimensions: creativity, visual input, and contextual range. Noteworthy improvements include processing over 25,000 words of text, accepting images as inputs, and generating captions, classifications, and analyses.

GPT 4 Capabilities

Chat GPT 4 capabilities include: 

  • Accepting images as inputs and generating captions, classifications, and analyses.
  • Capable of accepting images as queries and answering questions related to them.
  • Demonstrating more advanced programming capabilities, including code generation and natural language transformation.
  • Incorporating more advanced reasoning capabilities.
  • Being more creative and collaborative, proficient in generating, editing, and iterating on creative and technical writing tasks.

BERT architecture

BERT, an acronym for Bidirectional Encoder Representations from Transformers, is a transformer-based BERT model architecture extensively utilized in natural language processing (NLP) tasks.

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BERT Architecture Explained 

Comprising multiple layers, including feed-forward neural networks and self-attention, BERT is engineered to comprehend a word’s context within a sentence by considering the preceding and subsequent words.


Retrieval-augmented generation (RAG) is an architectural strategy that amplifies the capabilities of large language models (LLMs) by seamlessly integrating real-time, external knowledge into LLM responses.

This innovative approach enables language models to access the latest information without the need for retraining, utilizing retrieval-based methods for generating reliable outputs. RAG LLM architecture excels in various benchmarks such as Natural Questions, WebQuestions, and CuratedTrec, delivering more factual, specific, and diverse responses.

Falcon LLM architecture

Falcon LLM architecture pertains to domain-specific or enterprise-specific Large Language Models (LLMs) that undergo tailoring or fine-tuning to meet specific enterprise requirements. These models are finely optimized for finance, healthcare, legal, or technical sectors, ensuring heightened accuracy and relevance within their designated domains.

OPT architecture

In Large Language Models (LLMs), OPT architecture encompasses the utilization of specialized or application-specific LLMs, meticulously crafted to excel in specific enterprise areas. These models are optimized for distinct tasks or domains, such as finance, healthcare, legal, or technical sectors, providing elevated accuracy and relevance within their respective domains.

Enterprise LLM architecture

The utilization of large language models within enterprise applications and workflows defines Enterprise LLM architecture. Understanding key customization, optimization, and deployment aspects is essential for effectively leveraging LLMs in enterprise applications and workflows. This enables the creation of custom models and connections to external data and ensures the security and functionality of LLMs.

Final words

This exploration of diverse LLM architectures discussed the remarkable advancements in natural language processing. From the transformative Transformer architecture to specialized models like Falcon and OPT, these innovations cater to specific enterprise needs, marking a profound evolution in the application of Large Language Models across various domains.

Working with one of these LLMs? Be sure to add Aporia Guardrails to your security management and compliance stack to mitigate hallucinations and ensure AI reliability that builds user trust. 

Book a demo to learn how Guardrails can support your GenAI goals. 

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